Probably not so much the form factor
I think 8" would work better if the device came with a stylus and a keyboard attachment so the desktop could be used on the go. It wouldn't hurt either to throw in more storage and better CPU performance.
As it is these devices are destined to run in metro for the most part and that's where the problem is. Metro is quite a mature and usable touch GUI and the apps it ships with are very usable these days. However, the app store is a joke - the situation with 3rd party apps has improved but it doesn't bear favourable comparison to Android or the iPad. If I had money in my pocket to buy a 8" tablet, I'd probably drop it on a Galaxy Tab.
It's probably why Microsoft and vendors are looking to larger sizes where Android and iPad begin to look distinctly clunky and where a Windows tablet / hybrid makes more sense.
Biting the hand that feeds IT
