If you've spent any time trying to do any OpenGL work, you'll know the answers to these questions - and it's the same answer to all of them. The nvidia driver is the only one out there that actually has full OpenGL support. The Mesa guys will happily tell you how it supports the full 2.1 spec as well - and then mumble something about a software renderer - yes that's right, as long as you don't need any hardware acceleration, Mesa is the tool for you - or maybe we should reevaluate who the tool is... http://linuxhaters.blogspot.com/2008_06_01_archive.html