Startlingly much, actually.
I have met a whole heap of people who I first encountered online, for example people at the same conference as me who, like me, were tweeting about various events. I’ve also met friends of friends I’d be unlikely to have otherwise.
I have been invited to interval drinks by an orchestra to thank me for tweets about their performances.
And once after tweeting about a trip to Liberty to buy a tie only to find they were “between collections” I got an invitation from Liberty’s COO (whose wife is a Facebook friend – though I didn’t know she was related to Liberty) to come in, meet up, and get a tie.
And a recent tweet by me asking for recommendations for entry level Jazz CDs for someone with an interest in classical music brought forth a range of really good suggestions, including some from unexpected people.