Twitter has bought the UK Twitter client TweetDeck for $40 to $50 million, according to TechCrunch's Mike Arrington, citing a source knowledgeable of the deal. The popular Twitter client has been courted by two giants of the microblogging world, Twitter and UberMedia, which owns UberTwitter, EchoFon and of other Twitter-related startups. Arrington describes the decision as a "defensive" move by Twitter. "Adding TweetDeck to the UberMedia stable of products would give them too much leverage over Twitter, say our sources, and so Twitter made a strong defensive bid to disrupt the deal," writes Arrington.

Some are optimistic that the purchase will better synchronize TweetDeck with the micrblogging service. "Great, if this means it'll stop crashing on my iPhone," tweets Tekzilla's Patrick Norton. Others saw it as a savvy move. "As a shareholder ...I am happy," writes Howard Lindzon, the CEO of Stocktwits. Still others weren't so sanguine. "Time for Twitter to mess up my favorite Android Client," writes tech blogger Joshua Topolsky, with a hearty retweet from Joanna Stern.