Also installed the Windows 7 Beta on one of our Acer Tablets C110tci (1.25g ram, 30gig hd) tho the install would not finish using the firewire dvd drive that came with our Acer. I tried the install again using the HP 555s DVD drive we just got and it installed fine. Install times seem to be at least half that of vista.
I have not installed any apps yet, but the tablet seems to be running just as fast as the xp that was on there.
Tho the HP Mini install found the wireless card and did its updates automagically, the Acer only found the wired nic. I had to connect it to my wired network and did updates several times before it found all the drivers.