Diaz needs to get some wins under his belt in a lesser organization(s), if he does that then fine bring him back. But I think Robbie Lawler needs to be brought back, he's entertaining as hell, and since he lost to Diaz and then Tanner, he has won 3 straight away from the UFC, I hope they give him another chance.
I was actually suprised UFC brought Diaz back so quickly after the Riggs fight considering, from various reports, Diaz sucker punched Riggs because he felt that he should have won the fight. Grow up, be professional, and don't let it go to the judges. Here's hoping that Diaz gets he=is head screwed on straight, and has a long successful carreer, but not as successful as Lawler.