My view of touchscreen laptops:

I have an ASUS Transformer Infinity that I use for email, browsing, music, movies etc. I have the keyboard dock, but I use the touch screen more often than the touch pad. When I have access to both it becomes more apparent that some things are easier with the touch screen, though for others I prefer the touch pad. Move that there and select that is faster with the touchscreen than reach for the touch pad, start moving finger, visually scan for where the pointer was hiding, now move the pointer to where you want.

I have a laptop that I use for more demanding processes like chess or video gaming. I often find myself reaching for the screen in frustration. When the prices get better my next laptop might be touch screen.

I've commented before that I find my Lenevo X230 quite nice. Most of the time I just use it like an ordinary laptop, sometimes plugging in a full size keyboard and a nice mouse. But, sometimes, the touchscreen is awesome.

Disclaimer: My touchscreen is a stylus Wacom screen. You need to use the stylus.

So, what do I use the touchscreen for? Many things, but mainly drawing/practicing alternate character sets. E.g. to practice kanji using paper and pencil uses a heck of a lot of paper. This paper takes up space. Etc. etc. But, with my touchscreen (and rotated so it's flat like a tablet), I can practice as much as I want. I save the results, and then I can compare with previous times. Brilliant. I use software called Xournal for this task, as it seems to be the best touch-knowledgable software of its time for Linux. Other software I can suggest includes Easystroke for gestures (I've got it set to only listen to the stylus, and so it ignores the mouse).
Another use is using it to watch or read stuff while in cramped places (e.g. economy class on airplanes, or on buses).

Overall, I am very happy with my touchscreen.

If you can't use the keyboard to do everything faster then the UI is broken.

Touchscreens have limited usefulness, as do all input devices. But in cases they have enough benefit to be useful.

Their main advantage is being a re-use of device space - the screen and touchpad/keyboard now occupy the same space. So they're useful on phones, as they have well-established size constraints and a need for large screens but not much input precision. They're useful in POS systems or other semi-industrial applications, where they save a bit of space and are also more durable and user-friendly than other inputs (important when you base your hiring policies around minimum wage teenagers). It's also something that can be used one-handed more easily than other input devices.

Their downsides are limited precision/accuracy, are somewhat slow, and not scaling well to massive screen sizes (if my 27" monitor were a touchscreen, I think my arms would fall off after a minute of usage). That's why they aren't popular with desktops, workstations or servers - they need fast, precise input, and they either use large screens, or no screen. That's also why they are rarely a sole input device on gaming systems - the DS/3DS/Vita/WiiU all use traditional controls with the *addition* of a touchscreen.

Tablets are beginning to push against the precision/speed limits, and are beginning to use older methods via keyboard docks or bluetooth devices. Laptops have shrunk to the point where some, but not all, of them are suitable for a touchscreen. And hybrid devices are becoming an item.

I would put a touchscreen on small, ultralight laptops. Preferably also giving them some way to fold into a rough tablet shape, because that lets them be used with one hand holding, one hand operating, the device.

But on the larger 15" laptops, and the majority of 17" laptops, the rest of the device is just too large to be suited to a touchscreen. My own massive 9-pounder would be terrible with one.

I don't understand why people are against touchscreen laptops - nobody is forcing you to use the touch screen. You can still use the trackpad or a mouse or whatever. If you don't like it, just don't use it!

Why should I be for or against some product? Everybody should buy what they like and can afford. What do I care?

That way I don't feel so foolish when I thoughtlessly poke at the screen instead of using the trackpad like a sane person.

In the 1980's touch interfaces (and pen interfaces) were thoroughly discredited as a good input method for a desktop computer and nothing will ever change that. Nowadays, tablets have become a good implementation of a touch interface and fit a significant niche in terms of usability and function. But like everything else, once something becomes cheap, it gets foisted on us whether we want it or not, or whether it makes sense or not. Just like 20 years ago when everything got a clock put in it whether it made sense or not, and 10 years ago everything got a camera put in it whether it made sense or not, now everything has a touchscreen, whether it makes sense or not.

UI standards were a big thing in the early 1980s and I thought Microsoft was doing a really good job by adopting CUA and making a serious effort to adhere to UI standards. Even Windows 95, which introduced a lot of bad ideas along with the good ones still had a pretty consistent and well-thought-out UI. These UIs weren't fancy or very slick, but they made sense and people were able to use them well.

Then came cheap, high-res, high-color video cards, and suddenly by the late 90s, everyone went hog wild on the skeumorphic bandwagon. UI standards (and common sense) went out the door every time an interface designer broke the shrink-wrap on a new copy of Photoshop. Microsoft, of all people, eventually become the front-runner in pointlessly flashy (and usually much uglier) UI that broke all the standards but didn't supply a commensurate level of added usability or functionality. Remember how for about 5 versions, Windows Media Player kept devoting more and more screen real-estate to the border and pointless chrome and less to the actual, you know, media playing but, until it became a joke? I'm not trying to pick on Microsoft, but they are ubiquitous. Honestly, they were a little late to the game of pointless graphics and crappy UI, to their credit, but once they took the plunge, they went at it with gusto. The last good-looking UI they ever made, IMO, was Windows 2000.

Well, now that it costs almost nothing to put touch into every screen, we're going to get touch screens whether we want them or not. And Microsoft, again showing they've forgotten all the hard lessons they learned over the last 35 years when it comes to making software that is easy to use and consistent, will force us to adopt to the touchscreen paradigm whether we want it or not (i.e., Windows 8), and we'll have to suffer with it because they are still a monopoly. Now I am trying to pick on them, especially because I finally got a chance to use Windows 8 in the last week and I think it is easily the ugliest version of Windows since version 2. And Windows 2 was ugly because the technology limitations pretty much made it impossible for it not to be.

Yes, Apple will always have its niche of people who think they are more clever than the rest of us (or are just less stingy), and a few brave souls will wander the vast and wonderful frontier of Linux and friends (but to be honest, after seeing Unity and Gnome 3, it seems the bad UI disease isn't limited to the dinosaurs). But we are still in a place where the tail is wagging the dog and we have touch-screens not because they are the best solution, but just because they are cheap and make for a good checkmark on some marketroid's list.

I've been converted by the Surface Pro in the last couple weeks. Windows 8 seems like Windows 7 + annoyances on the desktop, but on a tablet it was instantly more useable in terms of navigating between programs, local content (to a huge extent), and internet content than my iPad or Nexus 7 have been. For my previous use cases, compared to my x230 running Windows 7 I'm happier with the Surface Pro about 2/3 of the time.

On top of that I've go a new capability that wasn't possible with previous devices: handwritten note-taking with the digitizer and OneNote. I've tried Evernote on iOS, which mostly fails because of the capacitive touchscreen + stylus experience. I've tried various pieces of software on my x230, but I find that half the time I don't have a place to set my laptop when I take notes and I end up taking most in paper notebooks. On the Surface Pro I take notes as easily as I do on paper via the tablet version of OneNote (it fills the every pixel on the screen with its drawing surface, whereas the desktop version doesn't quite get there) and those notes are then synced via Skydrive so they're available on all my devices. I like the hierarchical organization, which I never quite manage to do with paper, and also the very effective search, which shows me every instance of a searched term appearing in any of my notes despite my bad handwriting.

The Surface Pro is definitely not for everyone. Its battery life is comparable to ultrabooks. I get 5-6 hours taking notes, 4-5 hours on the web, using Office / Photoshop, or watching video. That's half what I can get on an ARM tablet (at twice the price!) but the ARM tablets just don't have the same capabilities. But I think for a decently big chunk of the populace, probably tens of millions in the US today, it's probably the best tablet available.

A couple final notes on using the Surface Pro to take notes at work: 1) A lot of people want to comment, usually saying something like they've tried to do something similar on an iPad but it was a bad experience so why does my black iPad clone seem to work so well? 2) People are most impressed with the ability to flip over the stylus and erase. For some reason this blows a lot of minds.

If you haven't spent a few weeks using Windows 8 on a touchscreen laptop, you don't know what you're missing. Aesthetically, the tiled homescreen could use some work. Functionally it is quite nice once you start using it.