Rick Perry's "birther" comments

A lead story on all the cable news shows last night was Rick Perry's vague endorsement of the birther theory that Obama was not born in the US.  I kept wondering why we're talking about this at all.  Besides the fact that no one with an ounce of political credibility seriously believes this ridiculous charge (so why is the media still giving it headlines???), but much more to the point, who cares what Rick Perry says?  He's no longer a viable national candidate and his poll numbers have totally tanked.  Nobody reports on Michelle Bachmann anymore, so why is this guy still getting any attention?