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Its a recent topic amonst theme developers and some headwya has been made in that areas. DCDezines is one of them, and incama.nl is moving towards that trend as well.
It's new as far as a concept goes to create incredable pages with css. CSS3 will raise that bar even more, so it's best to get on the bandwagon now as opposed to later.
There are many discussions here in the forums, but a thourough search will be needed.
Heres one post for starters, hopefully others will jump in, they're much more qualified then I.