If you head over to engadget you can get a preview of Windows 7’s features and overall look.  Some interesting tidbits came up about the systems that Windows 7 will run on.  At the PDC the audience was shown a netbook with a 1GHz processor and a single gigabyte of RAM, half of which was unused.  It will also support up to 256 CPUs (or maybe they mean cores?), giving you lots of room to expand or to use Larrabee perhaps.  The information is still coming, so keep your eyes peeled for more updates.
Will it always be 'Windows 7' or will it be shortened to 7? - General Tech  1