Disney acquired Playdom, maker of Facebook and MySpace games, for $563.2 million (with an additional earn-out of $200 million) in the end of July. Playdom had taken $76 million in venture capital, making it a seemingly very good investment for everyone involved.
Given that Disney's 2007 acquisition of Club Penguin seems to have done quite well and still no earn-out has been paid, the goals for the earn-out are likely pretty aggressive. Late last year Playdom had an annual revenue run-rate of $50 million and assuming good growth this year, it seems like Disney paid 6-7x revenue (excluding the earn-out).
Out of the four largest games publishers on Facebbok, two are now independent (Zynga and Crowdstar) and two are part of companies with other games/media assets (Playfish/EA and Playdom/Disney).