Fred touches on the idea that MySpace has begun losing users to Facebook, spurred by NimBLOG. The traffic stats suggest the opposite, as in the below graph.
However, I can’t help but agree with the point that the teen crowd is exceptionally fickle and I don’t know what unique characteristic MySpace has to keep them interested, and keep getting new users as new kids enter their teen years. Facebook has the university angle which will keep feeding the funnel.
UPDATE: Ben Casnocha had made the same call two months ago, reporting from the field.
Cem Sertoglu 
it may take a while for all this to play out in the traffic numbers.
my 15 year old prefers facebook but still uses myspace because some of her friends still use myspace
and the younger crowd is getting on the myspace bandwagon at the same time the older crowd is getting off
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