From New York Magazine:
Neither comment even brushes the level of questioning (or, certainly, accusation of cowardice) that was devoted to John Kerry's Vietnam record by the Swift Boat Veterans for Truth during the 2004 election. But Smith points out that they're part of a fringe trend toward deflating McCain's seemingly unimpeachable war record. Like Bush in 2004, Obama does not support the attacks and has always praised McCain's war record. But unlike Kerry in 2004, it looks like McCain is ready to go immediately on the counterattack.
Somehow, I don't think that Obama's convention will involve handing out ropes to bind other delegates with. Whatever the merits of Obama's response, he certainly didn't wait a week after anyone stopped making "controversial" claims to say anything. I somehow doubt that if someone does say McCain's experiences and recollections are bogus, they'll get nominated to be ambassador to Belgium, either.
You never know, though. I could be proven wrong.