What's hot this season for gifts? Retro and quirky

— -- Jewelry sales are up, but so are book sales. Superhero footie pajamas and racy lingerie are also big sellers, at least for certain demographics.

It's going to be a very merry — if not mystifying — Christmas when it comes to often-discretionary gift buying this year.

"Consumer spending behavior is much more stable than consumer sentiment," says PNC Financial Services chief economist Stuart Hoffman.

And people are indeed spending, often on increasingly pricey, and quirky, products. Apple was the third-most-popular website last month, topping Target, according to data out Friday by digital measurement company ComScore.

Looney Tunes, not mixed martial arts, are especially big at youthful retailer Spencer's, also home of Batman footie pj's.

Other trends:

•Retro. Some of the hottest toys this holiday season are throwbacks. Barbie and Legos are near the top of some wish lists and online searches. Spencer's CEO Steven Silverstein says lava lamps and shirts and sleepwear with Elmo, Cookie Monster and Teenage Ninja Mutant Turtles are big sellers.

•Tech-inspired fashion. J.C. Penney says hot sellers include Hoodie Buddies — hooded sweatshirts with a place to route MP3 player cords — and gloves that can be used with phones.

•Jewelry. Sales at independent jewelry stores were up 4.5% since January 2010, says financial data company Sageworks. Holiday sales at online jewelry retailer Gemvara are triple what they were in 2010. Macy's says earrings and gold and colored sequins on clothes are big sellers.

•Books. Sales at independent bookstores were up more than 15% over the Thanksgiving weekend, and bookstore websites powered by the American Booksellers Association were up 60% through Cyber Monday vs. 2010, ABA says.

•Lingerie. Market researcher NPD Group says undergarment sales overall were flat this year, but bra sales were up 5%. Urban fashion website Karmaloop says its lingerie sales were up 200% this season — especially bras and designs that can be worn as outerwear.

•Footwear. Upscale men's shoemaker Allen Edmonds has a boot in its top 10 most-popular styles for the first time. Men's boots are outpacing growth in sneakers at Karmaloop, too, and are up 450% this season.

"The most popular deal this year was a rare sale on Ugg boots, a 'want' by any definition," says BradsDeals.com founder Brad Wilson.