Christopher Beam's thoughts on McCain now saying that using Wright is legitimate:
...on the one hand McCain wants people to know he’s upstanding and above the fray and all that. But on the other, he’d be a fool not to use Wright against Obama. This tension is likely to dog McCain through November. Then there’s always the possibility that harping on Wright could backfire. The moment it stops being about patriotism and starts being about race, McCain could get burned as badly if not worse than Obama.
Wright has now made McCain's conundrum easier. Obama's too.