Los Angeles-based Rubicon Project, the online advertising optimization service firm headed by Frank Addante, is claiming this morning that the firm saw 270%, year over year growth in 2009. According to the firm, it served up more than 350 billion ads through its platform this year. The firm did not disclose any financial, but said it now has 150 employees. Rubicon Project's online advertising service helps publishers pick the best yielding ads from online ad networks. The firm is backed by $42M in funding from Clearstone Ventures, Mayfield, IDG Venturs, and the GE/NBC Universal Peacock Equity Fund.