Facebook users 'like' chatting about Halloween costumes

— -- Even Halloween is feeling the Facebook effect.

Out: individual, celebrity-of-the-moment costumes.

In: group, family and couple costumes that Facebook users and their friends can swap pictures of and gossip about on the social-media site long before wearing them out together on Halloween.

Among this year's hottest sellers for group getups: Crayola crayons, Monster High dolls, sexy animals, partying pirates and creepy zombies. Costumes rank as the biggest Halloween expense for young professionals, who'll spend an average $63 on costumes, the American Express Spending & Saving Tracker projects.

But the Facebook effect is hard to ignore. It's the first year that HalloweenCostumes.com and BuyCostumes.com are encouraging consumers to "like" costumes on their sites. "This way, you can let others know that you're staking a claim on a particular costume," says Travis Mattick, lead buyer at HalloweenCostumes.com. "It can have a viral effect."

Beyond Halloween, Facebook's already preparing for the day after Halloween — its biggest day of the year for uploaded photos, says spokesman Larry Yu. "Halloween is the social, visual and perfect stew that people want to share," he says.

•Group costumes. There are more than a dozen colors of Crayola crayon costumes at $26.99 to $28.99. The line is more popular with grown-ups than kids, Mattick says.

Group costumes featuring the cast of TV show Jersey Shore, Harry Potter characters and Monster High dolls are big sellers made by Rubie's Costume. "Facebook has helped to spread the word," says Howard Beige of Rubie's.

A fashion trend known as "steampunk" has emerged as the big group costume seller at BuyCostumes.com. These costumes feature vampires dressed in Victorian garb and decked out in aviator goggles, says CEO Daniel Haight.

•Family costumes. Entire families are dressing in themed costumes. The hot family seller at Rubie's is Super Mario Brothers, Beige says. Younger kids like the inflatable belly costumes of Mario, while fathers opt for Waluigi, and mothers favor Princess Peach. Prices: $19.98 to $49.99.

•Couple costumes. Couples are big on matching costumes this Halloween. Particularly popular at BuyCostumes.com are his-and-her zombie costumes that sell for up to $56.99, says Haight. "I'm convinced this is the year of the zombie."