My LS800 arrived yesterday (!). First impression: wow, that's small! But after getting a good look at it, I think "just right" is a better description. This is really the perfect size, and after a day of use, I can't imagine lugging around anything bigger.
Here's the first installment of pictures and comments.
The shipping box is subdivided into two halves: one for the LS800, the other for the accessories box:

To get a feel for the size, here's a couple of shots by a standard DayRunner medium-sized binder (which I really hope to replace with this!):
For comparison, here it is next to my (defunct) Casio E200 PocketPC:
And now with its new neighbor (when it's not on the road), the Mac Mini:
In that last one, that's an Apple Wireless Keyboard and Sony SDM-S74 17in monitor.
One of the issues mentioned in reviews is heat: it does get a little toasty. I actually had it shutdown on me. Interestingly, I was being careful not to block the (many) vents. I had it on the table but slightly (1") elevated at one end. The shutdown was not too graceful, either. The auto-shutdown came up and started a 1-minute countdown timer. Five seconds later, it came up and started another one! And then another... meanwhile, I managed to manually get to the Sleep command (the machine was running like molasses at this point). After letting it cool down some, I woke it up, and it promptly went back to sleep (one of the auto-shutdowns was still running, I guess).
Only other serious mishap has been with the screen controls -- DO NOT use the usual Properties... Settings.
Note the selected display is 800x600, but the minimum resolution is 1024x768. If you click OK or Apply here, it will set the device to 1024x768. The screen will automatically pan around, but your pointer calibration, well, isn't. I restarted and it more or less fixed itself; I think you could also do it through an option on the Motion Dashboard that brings up an Intel display manager.
The only other thing which is a bit irritating is the screen rotation. I like using it in portrait (I'm still debating which portrait position, but that's another story). Windows insists on displaying the login screen in landscape (although it sometimes mangles/crops a portrait-sized display into a landscape orientation). I can't figure out how it chooses which landscape to use, though, and when you get logged in, it can't seem to remember which portrait to go back to; it goes to the right one for a second, and then switches to landscape. Windows...