With the release for Mac OS X Tiger scheduled for Friday Microsoft has recently released some infomation about their Longhorn!
I don't think Windows users are in a hurry to upgrade their OS. Microsoft is always known for building vaprowares but I am sure we don't want shell out bucks to upgrade to the newer OS. The press release also notes that Longhorn can run in slower machines in XP like mode. If that is the case I would just install XP and live with that. Why bother at all for the new OS?
If Microsoft can give recommeded system requirements for Longhorn then it would definitely be a huge welcome.