—Quantcast: Adam Gerber joins as CMO of the online traffic rating and analytics company Quantcast. Most recently, Gerber was at Brightcove as VP-advertising products and strategy; his agency experience includes founding partner of WPP’s Digital Edge unit (now MEC Interaction). More here.

—Yahoo: Andy Baio, the creator of group calendar site Upcoming.org, which was bought by Yahoo, (NSDQ: YHOO) is leaving the company…he is departing after five years of working on Upcoming and two years after its acquisition by Yahoo. More here.

—Bebo: Bebo co-founder Jim Scheinman has left the company, and joined Charles River Ventures as an entrepreneur in residence (EIR). Scheinman will look at new investments in the consumer Internet, social networking and social media sectors, while working with the firm’s portfolio companies and evaluating opportunities for his own next start-up venture. Prior to Bebo, Scheinman was one of the first employees and head of business development and sales at Friendster. More here.

—Ensequence: Ensequence, the interactive TV company based in NYC, has appointed Peter Low as president and COO. Low was most recently EVP of cable distribution and marketing for MTV Networks and BET Networks, where he led cable distribution efforts for all 26 of the MTV and BET branded channels. More here.