Turning Email into a Social Network

The New York Times, TechCrunch and others report on Yahoo and Google turning Email into a social network. Email is a way that people connect, so why not use it to build a network?

I agree that this idea has potential (and in fact think they're a bit slow to realize this!). Here are two concerns I'd share.

1.) Will people want this stuff in their inbox environment?
2.) Might this lead to bloat and the MySpace effect?

I think they could do something very nice if they can navigate around these issues. Do you agree?