Twitter has notched another deal in its bid to expand from a microblogging site to a full-fledged media platform. BBC America on Thursday evening tweeted it had signed with Twitter for the first “in-Tweet branded video synced to entertainment TV series.” The companies offered no further information, nor did they say which shows would be involved, but the tweet noted that BBC America is home to Doctor Who and Top Gear. Earlier this week, a report surfaced that Twitter may be close to deals with Viacom and NBCUniversal for the site to stream videos and split ad revenue with the networks. The scant info on the BBC America deal reads like the tweet-branded video could be add-on content. Around 32M people tweeted about TV shows in 2012. Twitter already has partnerships with ESPN, Weather Channel and Turner Broadcasting System.