Today, mBlast has launched a free version of its mPact application, which determines the 10 most influential people across social media, news sites, and other online channels in particular categories. So, according to the press release, its tool doesn’t just give a “generic” score like “other first-generation ‘influencer’ tools.” We wonder who they could be talking about. Users can upgrade from the free version to mPACT Pro.

XYDO, a social news site that organizes news based on what’s being shared across Facebook, Twitter, and a user’s social graph, launches today. Mashable has a review here.

As we mentioned briefly yesterday, Twitter is acquiring TweetDeck for between $40 million and $50 million. PC Magazine suspects that Twitter wants to gain greater control of its apps. And our AllTwitter colleagues question what Twitter will do with the app. “Twitter doesn’t really care about owning TweetDeck. They only care about Ubermedia not owning it,” the site says.