Mountain View-based Twitter said Tuesday that it has acquired Bluefin Labs, a developer of social television analytics tools. Financial terms of the buy were not disclosed, however, the NY Times reports the price is around $100M. Bluefin Labs was based in Cambridge, mass., and was backed by R&D Bauer Ventures, Redpoint Ventures, SoftBank Capital, and Time Warner. Twitter said it specifically acquired Bluefin to help bolster its efforts to develop the Nielsen Twitter TV Rating. As part of the acquisition, Twitter will be shutting down the access to Bluefin's product suite beyond existing contract terms.