I'm excited about this news but a little scared also.
I think mac os' GUI was at its best in panther and it has gone all over the place with a lot of wrong choices (mostly iTunes)
Coincidentally, I went into the macheist site (advertised here in macrumors) and saw details about the Disco CD burning app.
"everything encompassed in a stylish, custom window that might offer an early peek at where Apple may take OS X's UI"
The app looks great http://discoapp.com/
if they make mac os look like this I'll be relieved and happy (so long as it's unified, maybe nothing is more important than this)
Disco is crap. Just use it for a few minutes and you'll absolutely HATE its UI. It uses transparency where transparency is not needed (Think 10.0 transparent title bars, except it's the whole freakin' app minus the title bar this time)
I hope to God/Buddha/Satan/Vishnu/Jeebu/Etc. Apple doesn't go that route.