Old news by now, but I am including the post by request to facilitate discussion.
Some see it as a way to maintain support among younger voters since they favor gay marriage. I think this puts more pressure on the GOP to come out strongly against gay marriage in order to differentiate the party on the issue. While I think that would be misguided and cut against them in the general election, I am pretty sure this will be a big deal during the primary season.
To better understand the legal issues involved, see this article which reviews the different types of scrutiny a discriminatory law must go through. Also here is AG Holder’s letter laying out the Administration’s position and support for a heightened scrutiny analysis.
To those who say equal rights is not linked with legal assessments of status, I say read the letter and this article.