Let's face it -- touch, just plain touch, has been around since the Apple Newton, and was workaday fare when it was called a Palm Pilot. And back in those days, around the turn of the century, even those 160x160 px screens and 16Mb of memory were good all-around workhorses. I had a couple of the Handspring PDAs, and later one of the Compaq palm-tops, and used them to death -- with the MessagEase keyboard, I could type as fast as I could compose, tapping and dragging the stylus; and I could do easy and accurate cursor navigation and text selection. With the PLua app, I could even code on and for the device (and have a single PalmOS app to prove it, for rolling various dice combinations for role playing games).
Fast-forward almost a decade, and I picked up one of the early and unofficial Android 2.1 tablets (the ViewQuest Slate); and though my skills on the MessagEase keyboard were somewhat rusty, I was still able to type faster than the device could keep up with, despite the ~3 iterations of Moore's law gone past in the interim. And the text selection model, combined with the necessarily fat-fingered capacitative screen, was pretty much unusable. While I could conveniently browse the web while on the khazi and compose terse forum posts, which was a plus over the old PDAs, anything that would involve quoting a section of another post just had to wait until I got onto a real computer.
This year, I've upgraded to an Asus Transformer, currently running JellyBean; and you know what? Despite the quad-core processor, the touch keyboard is still not as responsive as the Handspring one was, and is still way more intrusive. The big bonus to this device, though, is that it has a real physical keyboard and touchpad, which actually lets me select text in a way that isn't intrinsically painful.
So, what is touch good for? Well, even with the keyboard docked, scrolling pages is easier; and the multi-touch zoom makes it easy to expand web-comics so I can read the speech balloons. And I will prod at hyperlinks directly rather than use the pointer via the touchpad (except on really cluttered pages where the pointer precision is indispensable), because the tap-to-activate isn't in my muscle memory at all.
Overall, the device is something that suffices for me as a connection to the Wired when I'm on a cycling holiday, and don't expect to do more than read mail and blogs, and post a bit in the forums (or use it, at pinch, as a camera). But it's really a tool for snacking, rather than cooking -- for example, though I used the Asus while having coffee in bed this morning, I'm now composing this post on my 5 year old laptop running Vista, because it's still simpler to cut and paste hyperlinks that way, and the touchpad plus buttons are just like extensions of my will; and as such, I don't get the urge to reach forward and physically touch the screen, because my intent already has the same effect without conscious intervention, and with greater precision to boot.
And talking the transformation of will into reality with precision, these modern touch devices suck at accessibility. If you are in a state where you are left with just limited use of one hand (and not your even your preferred one at that), a touch device becomes essentially unusable, in a way that mouse plus on-screen keyboard manages to avoid.