So like all of you, I'm pretty upset about the Rick Warren thing. I think that Obama was wrong to invite someone who is so anti-gay. Now, I do think that Obama has a way to make up for this, by having the Rev. Gene Robinson offer an opening prayer...
Obama should have the Rev. Gene Robinson offer an opening prayer to begin the program. According to The Guardian, the ceremony starts with music. Gene Robison could offer a prayer before all of the other festivities begin. With Robinson offering an opening prayer, nothing will really have to be changed. Rick Warren and Joseph Lowery could still offer their respective prayers.
This would be a sign from Obama that he really does want to be the President of ALL Americans. If Rick Warren has a problem with sharing the stage with Robinson, he can not offer his prayer. This would also show that Obama is willing to hear from all Americans. America could see that even those fundamentally opposed to one another could agree to come together in at least sharing a stage.
UPDATE(1/12): Looks like Obama did just what I was suggesting!!