One can't help concurring with Scott Karp - Facebook for business networking is a tricky proposition...

"Yes, Facebook Platform makes Facebook infinitely extensible, but thecore, native Facebook apps and features are ABSOLUTELY UNCHANGED sinceit was originally designed for students to socialize.

"But business and professional needs are NOT the same as personal needs.I have no need to “poke” my professional colleagues or specify that ourworking relationship began when we “hooked up.” I don’t need to knowabout my professional colleagues what gender they are interested inmating with, or what they are looking for in a relationship, or whattheir favorite TV shows are — these things may be of voyeuristicquasi-social interest, but they don’t help me connect or collaborateprofessionally (other than maybe topics for idle — or embarrassing —chit-chat)."

I'd have to agree. A network like LinkedIn, whilst imperfect, is designed from the bottom up to facilitate professional-to-professional connections. Facebook is fun, but do professionals need to receive "zombie" invites from peers every five minutes?

There are, doubtless, opportunities on Facebook for professionals. But it depends on what type of business you expect to do once you get there (if you're in retail, widgets can help sell your stuff; if you're in advocacy, apps can held spread your message) - discovering and connecting with peers are some of the least likely business transactions to take place.