I say Liddell, unless Cotoure gets lucky in the first round. The most recent fight I saw with Cotoure he did really bad, and this was against a nobody(at least to me). In the first round he did ok, was on top mostly, but I guess expecting to have a knockout, he punched himself out. Next couple rounds he didn't really do anyhing and almost got KO'ed, but was saved by he bell. He did win, but not by much. He's geting old, 40 couple may not seem like much, but being a fighter it seems like its been pretty hard on him; his knees are in bad shape, his kicks had nothing on them
Liddell seems to be at his best now, so unless Cotoure gets him in round 1, which doesn't seem likely, I see Liddell winning by knockout. But you never know, one lucky shot, and it can go either way.
Edit: heres a cool compilation:
www.filecabi.net/video/top-ufc-knockouts-2005.html