At this point, it seems pretty clear cut – users are migrating to where ‘similar users’ are located.

It would be my guess those lines will end up being divided based on socioeconomic status – which is part of the reason I like the metaphor of social media dividing as ‘neighborhoods’ – it seems quite apt.

MySpace is often ignored. And really, it shouldn’t be. It has 100′s of millions of users – and while some are migrating to Facebook – a vast majority are not. That is a large market – and one that should not be ignored.

Does this mean MySpace is a good place for advertising. If boyd is right about user behavior, and there really are 100s of millions of active users – well, it’d be foolhardy to not at least use it as a testing ground, wouldn’t it?

Facebook started out with a core group of users from Ivy League universities, and social networks are built by people connecting to others who are probably like them.

Facebook built its site for reserved rule-followers. You can get any page background you want, as long as it’s plain white. Embedded video or music? No thanks. Sparkles and animated fonts need not apply. Perfect for drivers of Volvo, BMW and Saab.

Right from the beginning, MySpace was open to everyone. And that’s who came. Its design allows each user a totally customized web page – the digital equivalent of a tuner car or a donk, a pierced lip or super-long nails. Perfect for people who wouldn’t be caught dead in khaki slacks, a pale blue Oxford shirt and penny loafers, or even a belt anywhere above thigh level.