We've been hearing rumors for a while that Twitter was looking to make TweetDeck a member of its flock, and now, the blue bird crew has made it official. All Things D reports that the deal was done for between $40 to 50 million, and that TweetDeck CEO Iain Dodsworth will stay on to run the platform. In its official announcement, Twitter said it will continue to "invest in the TweetDeck that users know and love" -- time will tell if the new boss birdie is a boon or bane for the popular tweet tracking app.