That's probably because it's a Dell.
They'll install XP for you instead of Vista if you make a bit of noise, get in their faces, you know.
But really, Vista uses far more resources than it needs to. I always thought of XP Silver as something that grows in the garden too.
[q=Odaisé Gaelach]Wow, some of that looks incredibly like OS X. The Dock bar at the top of the screen, the way that windows minimize with sloping sides...[/q]
Most of the widgets you see aren't part of Beryl itself, but third-party programs. Some, including the various dockers are written specifically to emulate other operating systems' programs, like OSX.