For starters, it has a WXGA display (1280x800) which, when optionally backlit, gives us 400nits of brightness. That's more than the Fujitsu T2010 which, till now, had the brightest display (in the 300nit range, I think). It also has a capacitive touch screen which means you can use it with your finger as well as the stylus. And the 'capacitive' feature of the touch screen gives it the ability to tell the difference between a finger press and a palm press, which is really cool. Also, it doesn't use the lightweight Intel mobile graphics chipset like the rest of the tablet PCs in the market do: it uses the ATI Radeon Xpress 1250 system which is, apparently, better than the Intel one.
Then, it has both a trackstick and a touchpad, which should make it appeal to the widest possible customer base. And finally, though its standard hard drive is an 40 or 80GB 4,200RPM one, you can upgrade to either a 120GB 5,200RPM one or a 32 or 64GB Solid State Device (SSD) drive. Yes, that's an SSD drive. A drive with no moving parts so, in theory, its as fast as your RAM is!
Of course, all of this comes at a cost, with the XT's basic configuration costing $800 more than the Toshiba M700's (and almost $1,000 more than the Fujitsu T4200's). And we don't yet know how much more the additional features (like the SSD drive) will cost. Another negative is that it has a low-powered processor, with a 1.2GHz Core2 Duo being the highest you can go.
So, while it does beat the rest of its competition in some areas, it is slightly underpowered and is does cost quite a bit more. Lets see what the soon-to-come full hands-on reviews say about it. Who knows, all these additional features might just be worth their cost.
[Sources: Reports from Engadget, GBM, CNET, Tablet PC Review; First hands on review from Engadget]