I'd be very curious in the Transformer Book. I do dislike the concept that, coupled with keyboard dock, it looks like an ungainly beast that should otherwise fit in the "ultra portable" category.
If it's got an attractive price -- no more than the average price for Ultrabooks, please and thank you... preferably under $1000 for $900-1000 Ultrabook performance -- I might have to think about it more than I rightfully should. More importantly, it will depend on just how well the competition approaches the convertible concept. I could easily see myself taking a full Windows 8 (not Win RT) tablet around, sticking to the Metro apps, and keeping it coupled with keyboard when I know I'll want to make use of the full Windows desktop experience and the whole catalog available for x86.