Oodle has been describing itself as a “social classifieds” platform for some time, extending its reach via deals with local powerhouses such as AOL, Comcast, Cox, Media General, Freedom and Wal-Mart. Now, it is set to make the hype more of a reality with dramatic enhancements that will power Facebook Marketplaces.

The launch strives to leverage the social values of Facebook, and takes it several steps beyond earlier Oodle features, such as local car price comparisons. The site will start with personal goods. Housing and employment will be added in coming months.

Users of the new service have four options. They can sell, sell something, give stuff away or donate to charity. The charity angle is a powerful one — also embraced by Insider Pages, which makes a donation to charity for every written review. In Facebook’s case, users can choose to donate proceeds from their sold goods among 1 million charities that have partnered with Network for Good (i.e., “Nature Conservancy”).

“It is a virtual garage sale for charity,” says CEO Craig Donato. It also comes complete with a receipt for tax purposes.

While users may choose their own charity, more than 20 charities are highlighted on the site. Each has committed to helping get the word out to its own members.

In keeping with the social aspect of the site, Facebook not only lets users describe the goods and chosen charity, but also lets them describe why they are supporting this cause. “It is a big part of the conversation and building community,” Donato notes.

Other enhancements include some basic mainstreaming for listing goods. “We learned something. Don’t make them fill out long forms,” says Donato. Goods are also searchable, and locations can be configured (so that only my San Diego friends will bid on a couch, for instance). “We are asking ourselves how we can create an opportunity for our advertisers,” says Donato.

To be sure, the addition of Facebook is something of a coup for Oodle, which has also recently added AOL and MySpace (the latter, which has pre-existing classifieds, is still being finessed). The new social and charity angles also could conceivably put a mega-used goods forum such as eBay within its sights. “We are building a critical mass through the network,” says Donato.

While Oodle gets about 50 percent of its traffic via the network now, that ratio is expected to kick up to 75 percent within a few months. “Our partners are quite large,” notes Donato. “Last year, even without Facebook, MySpace and AOL, we tripled our traffic.”

Donato is giving his view of social classifieds at Kelsey’s upcoming Marketplaces conference March 16-18 in L.A.