CNN reports that "Anheuser-Busch is pulling an advertisement planned for this year's Super Bowl that would have poked fun at last year's infamous 'wardrobe malfunction' that exposed Janet Jackson's breast during the halftime show." Budweiser's web site is apparently showing the ad, but I suggest checking out one of the links listed a bit down the thread at Metafilter. One comment in that thread makes the somewhat cynical but altogether plausible point that perhaps this is all a publicity ploy by Anheuser-Busch:

Step 1 - Create false controversy. "Free speech" and "censorship" are usually a good way to start.
Step 2 - Revel in the free buzz as people trip over themselves to defend you and attack the other side.
Step 3 - Profit!

Who knows... In any case, the commercial is pretty funny and not at all offensive, so I think this is much ado about nothing.