lol...OSX on XP...ewwwwwwww , I'm an OSX guy and yes I use both..i tried skinning once or twice and its not cool at all..makes XP even worst...Seriously...You might want to try PearPC or OSX86 (even its iligeal to experince OSX) or get a real mac

Its just my 2senlah..don't bash me up..If you want your GNOME to look a like OSX , there are many skins for it and seriously it looks like OSX..the menus are on top (in windows its in the app) , but in GNOME its on-top of the Bar (a'la OSX style)

BTW , nice tip