Barbara Bush (Dubya's daughter, not his mother) has just appeared in an HRC video spot promoting marriage equality in New York.
In terms of Bush's actually influence, this isn't all that important -- Bush is only a political figure because of who she's related to; she's expressed little interest in entering the public sphere on her own terms (even less than, say, Meghan McCain -- another gay marriage supporter). But what it does demonstrate is that, even among Republicans, the youth are just gone on this issue. Support for marriage discrimination is nearly solely the province of older Americans. It's barely even a partisan issue amongst the young. I'm dubious that the leaders of the "Christian right" can arrest the inevitable here -- I'm wondering if even they are beginning to feel some fatalism on the subject.
In any event, it's only a matter of time.