A new name for XP and Vista mixture. Basically this windows lies between both of them. As vista is quiet havier and powerfull as compared to XP so may be that why it was decided by microsoft to launch another mid-way thing like Windows 7. It has graphical look like vista but loading and other performance resemble with XP. but over all being a hyberdization, its really gud. You can also call it a theme for XP of Vista. but graphics and visual effects are awesome. So do try this. You will really like dat. I dont found any time limit to register it or any other such thing to do. but I think its beta version which doesnt need activation or registration. The media player already has a lot of codecs to play Xvid and other file format. Windows media player is also fantastic. Media show is another feature owned from Vista. Built-in Games are also good especially those which are to be played in Media show.