Quote - With politicians, it's pretty much fair game across-the-board.  With celebrities, it's something of a gray area.  Paparazzi are always looking for that humiliating shot of Brittany Spears or of Lindsay Lohan that will net them a cool $250,000 payday from the National Enquirer.......which amounts to selling the celeb's likeness.  And it's done all of the time, without any legal consequences to the photographers -- much to the anger & irritation of many celebrities. 

This is due to a loophole in IP laws allowing Journalistic/News works (on any media) as exempt. Celeb gossip does count as journalism, as do blogs and websites under certain conditions. They're not selling the celeb's likeness, but instead they're selling journalistic recordings (be they video or photographic) that happen to concern said celebrity.

That however is way tangent to the main point of the original post - the commercial sale/reproduction of someone's name and/or likeness. Try to do that on a celeb (and be noticed)? You'll have lawyers crawling into your rectum with summonses in their hands, and money on their minds.

While legally, you can simply change the name and be fairly safe, (yes, this is true), let's be practical about this for a minute. Joe Poserdom isn't likely to be a bazillionaire with a retained lawyer on speed-dial. The celeb who gets miffed at his or her likeness being sold OTOH about will likely have generous amounts of money and dedicated legal assistance on tap. The discovery phase of any lawsuit would likely bankrupt a typical Rendo merchie - let alone the suit itself, and letting still further alone any appeals processes.

To put it in perspective, let's do a hypothetical. I build a morph that looks dead-on like a certain female celebrity. I name it "London Motel6" and sell the crap out of it. Pervs and artists everywhere rejoice. I start to make a really big pile of dough out of it. Then a C&D shows up. Rendo would likely drop the product from RMP like it were a radioactive potato about to go critical just to steer clear of the whole thing - that absolves them under DMCA Safe Harbor provisions. The celeb is not impressed. You see, someone made a hyper-realistic render of a chick that looks just like her doing self-degrading things to a mesh that looks exactly like George W. Bush. Now she wants damages. Her lawyers want a new Jaguar apiece. Rendo is clear of any lawsuit. The artist who put that image together is anonymous, and nowhere to be credibly located on the Internet. Guess who that leaves as the target?  Right or wrong, I would now have to fund a defense against the thing. I do pretty well financially, but Lord knows I don't have that kind of bank...

Quote - This is semi-related -- google is planning on implementing changes to their mapping services that will blur the faces of people in street scenes --

Now this one is closer. IP laws and photography (as well as video) usually require model releases from anybody clearly depicted and individually identifiable, except under very narrow circumstances (like Journalism ferinstance). Of course you can ignore that, but you risk having the person depicted suing the crap out of you for damages (or royalties - depending).

/P