From eMarketer, via VentureBeat.
In summary still rising fast, but not quite as quickly as they had thought previously. $920m last year.

And Myspace is the premier destination, although Facebook is taking market share.

Note also that widgets only accounted for $15m last year, and will still be small this year.
Finally, as Venturebeat points out social networks make money via ecommerce and other areas in addition to advertising and therefore these numbers do not equate to total revenues.

Interested in what ‘Widgets and applications’ means and what happens when a widget goes into an ‘Other destination social networks’ (or in Facebook or MySpace for that matter).
Also – any growth predictions?
All good questions Ivan. I guess this is revenues earned by widget companies, including Facebook applications. Those widgets presumably appear on blogs and profile pages everywhere.
I haven’t seen any growth projections beyond the $15-$40m 2007-2008 cited above.
Nic, your headline is misleading. This is a large subset of social media as it ignores blogs and seemingly web2-y video/photo sharing like youtube.
tks Scott – will correct