good idea. yesterday i put a spare hd into my t43, installed jaunty and tried my luck with the normal and blob-drivers for the oooooold ati radeon m22 x300 rv 370 whatnot.
the "experience" was very much like "i will never again buy ati, or amd for that matter".
well, maybe i'll chuck the spare hd in again tomorrow and dist-upgrade to karmic. sounds like worth a try..
btw, changing sources.list, the simple way:
perl -pi -le 's/jaunty/karmic/g' sources.list
-- tee
well, needs some more, to edit all sources.list files, but is definitely nicer than sed 
-- phai
after dist-upgrading to karmic, i just put my original hd back in. it works, but the current blobdrivers are faster with 3d stuff. i guess i'll wait with dist-upgrading.
the radeonfb (and most other cardspecific fbdrvs) most of the time gave me a terribly slow console; also the -rt-kernels refuse to show any text console and only work with a graphical login. bad for ppl like me who dont always startx..
i normally go for vesa modes, vga=791 is fast and "small" enough. one exception is matroxfb, because:
screen
mplayer -vo mga_vid -blabla
on a 4:3 screen, i can watch movies and do some work at the same time, without X
--tee