I agree with greenjumper. As someone who actively works in his campaign, I can tell you that we are very proud that he has made these remarks.
Those who are against gay marriage are not normally Obama supporters anyway. It has energized his core supporters.
Just because he is personally for gay marriage doesn't mean gay people will be getting married soon. But it does let them know they have a president who gets it and realizes the importance of this civil right.
I was born to be a pessimist. My blood type is B Negative.