So here's the deal about touchscreens and Windows 8. There are lots of x86 touchscreen devices available that can run Windows 8. This is because Windows 7 had pretty good support for touch and multitouch and so more laptops and all-in-one desktops made their way to consumers. I've used an HP all-in-one Touchsmart 610, a Sony VAIO L Series all-in-one, a Samsung Series 7 Slate, and a Lenovo ThinkPad X220 tablet. Each of these machine was designed for Windows 7, so their CPU and memory configurations; their keyboards, trackpads, cameras, and other inputs; and their drives and ports are all very compatible with Windows 8. They're both compatible in terms of giving you decent performance and in terms of available drivers. Add to that a touchscreen and you might think you've got yourself a perfect Windows 8 kit. Unfortunately, it's not quite that rosy. While almost all of the machines I've tried were pretty much fully driver-compatible with Windows 8, and all of them had plenty of horsepower to drive Windows 8 with great performance, the touch experience ranged from absolutely unusable to wonderful.
Microsoft explains this quite well over at the Building Windows 8 blog. What it boils down to is that touchscreens that were built for Windows 7 focused on accuracy and increased capabilities (like multitouch) in the main work area of the screen at the expense of touch sensitivity and accuracy at the edges of the screen. That made fine sense in the Windows 7 world where most of your work takes place away from the edges. Unfortunately it can be a huge problem with Windows 8 because basic Windows navigation requires swipes that comes in from the edge of the screen and with all apps running in a full-screen mode, you're far more likely to find yourself working near the edges.
Another problem with some of the Windows 7 touchscreen devices is that they have giant raised bezels. Even if a machine has decent edge sensitivity in its touch panel, if you cannot easily swipe your finger from off-screen to on-screen, you may not be able to navigate Windows well.
So, what have I learned over the last few months of testing various configurations. Let's go from best to worst:
The Samsung Series 7 Slate (tablet) is really outstanding. It has edge detection that hasn't failed me once. It's got an edge-to-edge glass face so your swipes from off-screen to on are a breeze. It's got 8 finger multitouch so all Windows 8 touch gestures are fully supported. Finally, as you pan around, the content "sticks" to your finger really well and there's no problem selecting text with touch and drag. I'll also note that this x86 tablet is something of a beast. It comes with a 1.6GHz Core i5-2467M processor, 128GB SSD, 4GB of RAM, and a 400 nits, matte, 11.6", 1366 x 768, LED backlit panel. (Oh, and yeah, and it's got a fan ;-) Teamed up with its Slate PC Dock and bluetooth keyboard and you've got a pretty compelling Windows 8 device.
The Lenovo X220 Tablet Convertible is also excellent. Edge detection is solid. The 1366 x 768, 300 NITs bright panel is pretty nice, though a bit glossy and reflective for my taste. There's no raised bezel to get in your way. Swipe and drag gestures really stick to your fingers and the 5 finger multitouch covers all of the most common gestures. It's possible that you'll encounter apps that need more than 5 finger touch, so if that's a concern to you then you should probably wait for the next generation from Lenovo which I'm sure will up that to ten or more. The X220T is the only touch laptop I've tested but if you know ThinkPads, then you know this machine. It's tough and practical with plenty of configuration options. It's not beautiful and it's not light-weight like the latest crop of UltraBooks, but if you want a machine with great inputs (nice multitouch and the best keyboard in the business, IMO) it's a fine choice for Windows 8. I'll note that it also works great in the Windows 8 Classic mode which is basically Windows 7 with a few tweaks.
The Sony Vaio L Series all-in-one machine is OK on Windows 8 and I'm hoping it can get slightly better with touchscreen driver updates. The PC has a 24" screen with glass that extends about an inch beyond the LCD on all sides so it doesn't have the raised bezel problem. (Though it does have a raised plastic bezel, it's far enough away from the screen that it's not a problem.) Sony also brags of a touch technology that extends beyond the edge of the LCD to provide off-screen gestures, but there's no support for that in Windows 8 yet. I'm hoping that Sony or MS can make a driver update that takes advantage of that to improve the screen's edge detection. The touchscreen panel has several shortcomings. First, it only supports 2 finger gestures. This means that basic Windows 8 gestures like pinch to zoom and turn to rotate work, but that's really not enough. Also, it doesn't have great edge sensitivity. It's possible to learn how to position your finger just so as you swipe in from the screen edge to get a pretty good hit rate, but that's less than ideal. For those of you who have this machine or are thinking about getting one because of its other great qualities, like a Core i7 quad-core 2.50GHz processor, NVIDIA GeForce GT 540M GPU with 1GB RAM, Blu-ray player, 8GB of RAM, built-in TV tuner, and all around good looks, here's the trick to making it work: you can't use the tip of your finger. You have to use the face of your finger (where your fingerprint is) and you have to land your finger with some of it off-screen and some onscreen. For the swipe up and down gestures to raise the application toolbars, you don't actually swipe. You simply press your finger across that boundary. For the swipe in from the right, you do have to swipe in some but it helps if you have a very slight pause after initially pressing your finger down (again, with about half of your fingerprint off-screen and half on.) You'll see the very edge of the Windows charms bar become visible and if you start your swipe then, it works great. I know that sounds awful, but once you do it a few times it's pretty easy.
The HP Touchsmart 610 is a pretty nice all-in-one PC for Windows 7 but it's an absolutely horrible Windows 8 PC. The PC guts, including a 3.4GHz Core i7-2600 CPU, 8GB of RAM, Blu-ray, built-in TV tuner, and NVIDIA GeForce GT 425M GPU with 2GB RAM, are all pretty awesome. The reclining hinge that transforms it from a vertical orientation to a near-horziontal surface is actually quite nice. The machine has great (and very loud) speakers. The 23-inch, 1920 x 1080 panel is bright and beautiful. Unfortunately, the combination of limited 2 finger touch support, a giant plastic bezel, and just awful edge detection make Windows gestures simply impossible. I don't mean hit or miss; I mean impossible. There is no way to use this machine in Metro effectively without a mouse and keyboard. If you have one of these machines, I encourage you to keep it running Windows 7. I like the 610 a lot, but it's simply not Windows 8 ready.
One final note. Windows 8, even Metro, works fairly well with a mouse and keyboard. I have it loaded up on a bog standard ThinkPad T510 and the keyboard and trackpad/trackpoint controls work to navigate the system and use most of the apps and features just fine. It's not the preferred mode, but it's also not impossible. If you tried the Developer Preview that Microsoft released at Build last year, and were disappointed at how poorly the Metro experience integrated keyboard and mouse controls, the Consumer Preview has come a long way.
I've got a couple of touchscreen monitors on order, and as soon as I've had a chance to test them out, I'll blog and let you know how that goes.