Personally, I think Warren is an inspired choice. Choosing him extends an olive branch of sorts to the conservative right. They should appreciate the enormity of this--I can't think of a conservative who would have acted in like manner (I'm not saying there aren't any, but none in the public eye come to mind). Warren's role at the inauguration signals to the right what Obama said in his acceptance speech on election night, "I hear you." He understands clearly that he is president of all the people, not just those with whom he agrees or those who voted for him. Warren is offering a prayer, not policy. Billy Graham did the same.
Rick Warren is not a bad person. He is not arrogant or rude, and perhaps more importantly, he does not demonize those with whom he disagrees. He is a man of clear and strong convictions, passionate about his faith and about sharing that passion with others so that their faith may, in turn, be enriched. I think that's a good thing. He is also opposed to gay marriage. His understanding of scripture leads him there. I do not believe, however, that this belief defines him as a person. Each of us is greater than the sum of our parts and our beliefs. It would be one thing if Rick Warren was on a crusade to persecute gay, lesbian, bi-sexual and transgendered people, but he's not. He is simply like many other conservative Christians (and non-Christians) that hold this particular view.
Obama has been amazingly expansive in his view of how to equip his administration to make the best choices for what is good for the American people. Whatever his own views on particular issues, he has the wisdom to understand that sometimes a path that diverges from the course he would like to set will yield the greater good. His selection of Rick Warren reflects that thinking. Let's embrace Obama's wisdom and move on. There are far, far more important things to spend our energy on.