The Super Bowl of advertising begins in a few hours, and that means: Talking babies, driving chimps, flying Pepsi cans, someone licking another man's fingers (don't ask, but Doritos are involved), and Justin Bieber and Ozzy Osbourne. Some people will also reportedly watch some football.

There is nothing quite like the spectacle that is about to unfold, but it's also big business with a certain degree of risk attached. At $3 million per 30-second ad, that risk is self-evident. But what exactly is different about this year's commercial bonanza? Plenty. Here are some of the trends:

Celebrity, Celebrity, Celebrity. The famous or formerly famous have found their way to Super Bowl ads since the event began. This year, Eminem will star in two (Lipton and Chrysler). Richard Lewis and Roseanne Barr hope to do for Snickers - or their careers - what Abe Vigoda and Betty White did for theirs last year. Jillian Michaels and Danica Patrick are in a GoDaddy.com ad that has already gone viral. Kim Kardashian is doing a series of ads for Skechers. Bieber and Osbourne may well star in the most-talked-about ad of the game, and year - or so sponsor Best Buy fervently hopes.

Bob Horowitz, producer of CBS' annual "Best Super Bowl Commercials" specials, says the boom in celebrity endorsement reflects advertisers' need to generate pregame and postgame buzz for their expensive spots. "Is Snooki next in 2012? I don't think so, but it is definitely a trend," he says.

Cars, Cars, Cars. There will be a huge boost in car commercials. Reason: the improved economy, or so car advertisers hope, and more brands. Last year's auto advertisers were Audi, Chrysler Dodge, Honda, Hyundai and VW. This year: Audi, BMW North America, BMW Mini, Chrysler, Hyundai, Kia North America and Volkswagen. Mercedes-Benz, with one major 60-second ad (yes, that's $6 million) is new to the game. General Motors, which was off last year's game, is back with a roar: Five spots for various brands. The commercial for the Camaro has been released on the web, and stars Bumblebee - yes, another celeb - from "Transformers." (The car is yellow, too.)

Volkswagen's so-called Darth Vader ad for the Passat - which has debuted online - has already been among the most buzzed-about ads. The concept is simple: A small boy in a Darth Vader costume, who thinks he turns on his family car (but it's actually his dad, using a remote control from inside the house).

Facebook, Facebook, Facebook. Super Bowl XLV will be remembered as the year that social media - particularly Facebook and Twitter - infiltrated many commercials. Part of the reason is the huge cost of the spot itself.

"It's ridiculous to think about it as a 30-second ad," says Tor Myhren, president of Grey New York, who created the E*Trade "talking baby" campaign, which is among the most memorable in Super Bowl history. "You have a two-week lead-up with social media buzz [and then] you've got the postgame echo effect, which is huge now in the digital space with viral videos, social media and Twitter."

Bryan Gonzalez, director of the social and digital media technology center at the University of Southern California in Los Angeles, which advises movie-company advertisers on social media, says companies use the Super Bowl as a broad-based "platform to get consumers to follow your brand on social media. When you see a 30-second spot, it's here and then gone. But with social media, if you 'like' something to your Facebook page, that stays there so that advertisers can keep sending out those messages via those channels to those followers for a week or a month."

Gonzalez says most advertisers will append "follow me" Twitter or Facebook logos to their ads to get followers, but are mostly using contests to build social media buzz.

Example? Mercedes, which will give away two cars in a Twitter-based promotion; its ad stars Sean Combs. BMW is using a Facebook tie-in in which a viewer will win a two-year lease on a BMW X3.