I don't see how this is a bad trade for OKC. As many others have said, Harden is a bench player, so to get two first round picks, plus a potential third, it seems that OKC made out like bandits.
Plus, with how well they develop players (like Harden), I think OKC still represents the West in the Finals this year. The Lakers look good on paper, but Howard doesn't add anything different than what they lost in Bynum, and Nash isn't the shooting type. Bryant will still shoulder the responsibility of carrying the entire team.