I have a friend who's using Live 4 for djing and has "dumped his turntables" "
(c) LCD Soundsystem
Mixes of his stuff can be found at
www.drum-aberdeen.co.uk and there's huge discussion about all Live setps at the ableton forums
http://www.ableton.com/index.php?main=forum.
There's even a wee bit about Darren Price and Underworld who's using Live