Bezos Expeditions, the personal investment firm of Amazon.com's Jeff Bezos, has seen an exit out of its investment portfolio this week, with the acquisition of San Francisco-based Kongregate. Videogame retailer GameStop acquired Kongregate on Tuesday, but did not disclose financial terms of the deal. Kongregate operates an online social gaming site and community. The company was venture backed by Greylock Partners, Bezos Expeditions, and other angel investors. Bezos was an early investor in Kongregate, investing around $3M in the firm back in 2008.