It looks better from a designer point-of-view. Less blue, transparant toolbars.
But the rest is shit. Longhorn is pumped full with useless crap and looks like an overgrown Windows Media Player. You might as well call it "Microsoft Windows Media Player 10", just as you've might as well called Windows ME "Internet Explorer 7".
Just look at
this one. 80 GHz of RAM? Sure... I guess you get super-ultra-DDR-RAM v. 6.66 bundled when you buy Windows Longhorn Professional...
And what's up with that "Professional" crap? At least Microsoft tried to form a little difference in with Windows XP between the "Home" and "Professional" edition. But Longhorn's Professional edition looks like Fisherprise to me. How am I supposed to do professional things like rendering 3D movies, Photoshopping etc. when all those useless Microsoft crap keeps hogging up the recourses. Microsoft should make Longhorn more light-weight before trying to sell this useless piece of crap.