So you think Facebook’s growing rapidly, huh?  Well, check this out. Nielsen just released its latest ranking of the top social networks (for the month of October 2007), and it shows LinkedIn grew at a significantly faster clip than any of the top ten — even oh-so-hip darling Facebook. Of course, these numbers reflect usage at both home and work, and the latter is the traditional stronghold of professional network LinkedIn. Socntwksgrowth
But Facebook’s made no secret about expanding its user base into the adult working world, too — not just college kids passing around party pix.

What’s surprising is that, even with all the rapid — and rabid — Facebook adoption lately by us professionals (yes, I’m hooked, too), LinkedIn is growing even faster. Hipness is not everything, it seems — functionality matters, too. And LinkedIn has built up a pretty good stronghold in the professional networking/recruiting/job search space. (And you have to love founder Reid Hoffman also having a nice stake in Facebook as an early investor.)

Another reason LinkedIn may be scoring bigger growth: I’m not aware of companies banning it at work, but I certainly have heard that to be the case with Facebook inside some firms.
What’s your experience?  Should either of these sites be banned at work?  [The nerve of these employers, thinking people shouldn’t be searching for new jobs or sharing party invites when they’re supposed to be working…  :-)]

UPDATE (Thanksgiving Day, 11/22): Oh, this is too funny. GigaOM just posted Giving Thanks for…Facebook?

UPDATE (11/23): You have to love this juicy tidbit via TechCrunch UK…. Rumour: NewsCorp to Buy LinkedIn.  I think it could very well be true — I agree with one of the commenters that LinkedIn + the WSJ could be a great combo.