This ad works on a number of levels:
Why compare Obama to Britney and Paris in particular, you might ask? McCain's Roved-up campaign manager justified using Britney and Paris because they are the "#2 and #3 celebrities in the world." But is that right? I mean, not to be mean to Britney or anything, but they aren't really current, are they? Paris and Britney is the best they could come up with? Really? Talk about an admission of utter cluelessness. Has McCain ever heard of Angelina Jolie and Brad Pitt? They wont leave them alone anywhere. Brangelina can't get privacy in the depths of freaking Africa! No one would give a damn about over-the-hill Britney on an average Swedish street.
Also, Brad Pitt is the Girlfriend-Chameleon!
Of course, the problem with using Brad and Angela is that they're unavailable, aren't they? They're (currently) happily married. By contrast, Paris and Britney have both had their genitalia on the evening news. It's just like Harold Ford and the Playboy Mansion "Call me/Blond Slut" ad. To me, it sounds like shades of "Where All the White Women At?"
Combined with the presumptuous narrative they've been pushing since the "Didn't Visit the Troops" bullsession was called a lie by everybody (Republicans included), you get the components of the uppity-negro racist template. As Rove said, Obama is the too-cool guy at the country club with the beautiful (white) date on arm, lazily smoking a cigarette and snidely commenting on the other, more decent guests. The message, to those who can hear it, is "People like Obama should know their place."
It is possible all of this slipped by the advertising mavens, despite their curved editing talons and eagle-eyed examination of every frame of product they put on TV. John McCain may be so colorblind and pure of heart that he doesn't see the racist caricature in which he's engaging. The nail in the coffin - the thing that proves the racist tones this campaign has adopted - is that John McCain has done these things himself, and is not being viewed as presumptuous. John McCain has met with foreign leaders. John McCain has given speeches to foreign audiences, despite the fact that he is not yet president. John McCain has called himself "President McCain," and given an entire speech predicated on his successful first term. John McCain has said that he didn't always love this country. And yet, despite these congruences, no one has called John McCain uppity.
If you must find a difference between what Obama and McCain have already done, then one does present itself. Obama has done the same things McCain has, except better. Way, WAY better (see Fudge Haus vs Berlin). I suppose that's the real problem. How dare Obama, that outsider, have the audacity to make McCain look like such an ineffective relic, barely a part of the campaign that he has sold his soul to get the nomination for.