Dow Jones' Media Memo writer Peter Kafka says he's got the "final" number for Google's recent purchase of online advertising system Invite Media: $81 million. (A source to Google tells me "$80 to $85 million.") 

"It was a great outcome for everyone involved," Chris Fralic, partner at Invite Media investor First Round Capital.

If so, that's a pretty good three-year return on the $5 million invested in Invite by a couple of funds backed by Google's sometime-partner/sometime-rival Comcast Corp., by First Round, and by other investors, in the firm, founded by ceo Nat S. Turner and three of his classmates at the University of Pennsylvania. Previous story here, blog item here.