the biggest problem of quake live is that, well, it's vanilla q3a. i still play CPMA mod and got used to its behavior and physics, fast weapon switching, all the good things, you know...
when the beta test was still at the closed stage i played maybe a five or six clan arena matches. boy, it felt like a cripple even trying to bunny hop and strafejump.
also kinda sucks that so far they have very few totally new maps (it has every vq3a map minus q3dm0 and tourney5, couple from team arena although that addon was complete crap) and the old maps were somewhat retouched to have quakelive logos in 'em, etc. lack of good maps... there were not so many really good arenas in original q3a to begin with.
and now, when they went to the open beta testing, shit, the queues! like, 13000? the best bit is the online statistics though. some people also don't notice the "fullscreen" option too.
so yeah it's basically q3a. with online matchmaking and statistics. id is probably testing this online thingy on a 10 year old game and they will probably include this feature in their following games (doom4).
so... i'd rather play challenge pro mode arena.
p.s. don't care about the visuals, q3a looks fine to me. i prefer eye candy in the single player. but - they removed the gibs. now instead of fountain of blood and pieces of meat you get wussy-ass sparks. wtf.