http://code.google.com/p/blueprintcss/

It's a new CSS framework that aims to reduce the pain of creating a cross-browser grid-based layout. It's not done yet (at version 0.3 and still some browser bugs to work out) but it's shaping up to be pretty nice.

So are you using blueprint, or any other CSS framework like Yahoo UI? Do you find it reduces your development/debugging time, or does it just create a new layer of problems?