3 ) yes NVidia could well have had drivers out longer but they only seem to work with the
largely obsolete 2.4 kernels (and even then that's hard)
I've never had problems with nvidia. It was straightforward to install on 2.6 kernels with:
Debian etch, debian lenny, fedora 8 (and now 9), ubuntu feisty, gutsy, suse 10.2,
pclinuxos, sabayon. Besides, solaris 10 and freebsd 6.3.
I've never used ATI with linux, but If ATI support was better it would mean that it must install automatically