• by Sarah Mahoney  @mahoney_sarah, February 14, 2011

Barbie and Ken have ironed out their differences, and after a seven-year separation, are back on again, with Mattel announcing a limited edition "She said yes!" gift set to celebrate their reconciliation.

While the romantic announcement was timed for Valentine's Day, more cynical observers might think it's a career ploy from the 50-something fashion doll: It coincides with the opening of Toy Fair, the industry's biggest annual event, now underway in New York.

The El Segundo, Calif.-based toy marketer says Barbie updated her Facebook status to "In a relationship," officially ending the seven-year break. (Fans will recall she ditched him for an Australian surfer.) Ken has been tweeting all month about his romantic gestures, the company says, "to prove that even though he is plastic, his love is real." The couple also merged their Facebook pages.

Ken even got a new look: The Wall Street Journal reports that the company's "Celebrating Ken" party at Christie's auction house included six new looks, like "Concert Date" and "Picnic Date." Models with really good hair and tuxedos greeted guests.

Mattel also unveiled its newest interactive Mickey Mouse Plush toy, with Rock Star Mickey. A partnership between Mattel's Fisher-Price and Disney Consumer Products, Rock Star Mickey is a follow-up to last year's hit, Dance Star Mickey. Besides swinging his axe to such tunes as "You Really Got Me," he's got stage-worthy moves, including "a mouska split."

Not to be outdone, Hasbro is introducing Let's Rock Elmo, which it describes as "the most innovative and engaging Elmo toy yet."

Meanwhile, Hasbro, the No. 2 toy marketer, is also showing off a new line of building sets called Kre-O, directly taking on Lego. Kre-O sets will allow kids 6 and up to build things with other Hasbro brands, including Transformers.

Lego Systems is unveiling open-ended building sets, with themes such as ninjas, aliens and a desert quest.

Overall, the Toy Industry Association, which sponsors the annual trade show, says it expects more than 100,000 different products to be on display, and that many of the year's toys follow these trends:

• Simply Social Physical toys that work with apps and other e-connected toys, as well as socially aware toys that encourage kids to be "everyday heroes"
  
• Cent-sational Toys Mini toys with mini price points
• Performance Play Challenge bodies and minds with active sports, logical thinking, and motion-sensor technology
• Design, Discover and Learn Products that emphasize "camouflage learning" (learning is fun) and "geek chic" (learning is cool.)