windows 7 supports USB Monitors
Code:
http://www.google.co.uk/products/catalog?q=usb+monitor&hl=en&client=opera&hs=ylt&rls=en&channel=suggest&prmd=ivns&resnum=1&biw=1366&bih=639&um=1&ie=UTF-8&tbm=shop&cid=1046636826324764467&sa=X&ei=7Z3gTdX3EZHt-gbcm4i9Bg&ved=0CIQBEPICMAA
so I would say yes, it would be supported. (only difference between usb monitor and usb projector is the way they display the image)
EDIT: buy it from the local store and see if it works. if not, take it back saying that it doesn't work with your pc.

win/win situation.