UMPC Fever has a forum member who installed Windows 7 on a Fujitsu U2010, which worked great, from the included screenshots. They were able to use Vista drivers, and it was supported better than XP. They mentioned it was faster than Vista.
Ultramobile PC Tips had news of another forum user on a Spanish-language site who had installed Windows 7 on a Gigabyte UMPC U60. They reported that it booted faster than Windows XP Tablet PC Edition (SP3) and runs just about as fast overall. It also had no problems with the U60’s WiFi (Vista did). (via SlashGear)
Meanwhile, Computerworld had word from Microsoft that Windows 7 would run on netbooks with at least 16GB Solid State Drives (SSDs). Windows 7 will need 8GB for normal operation, with 8GB for installed applications and user data. They claim that it will have a smaller install than Vista, and that the 16GB makes for “a good Windows 7 experience.”
A Microsoft employee did mention that MS isn’t planning on supporting booting up from USB flash drives, something that many people have used to install all sorts of OSes on their netbooks.