There’s no shortage of angles when it comes to this morning’s news that Microsoft will investment $300 million in a new Barnes & Noble subsidiary to take on Apple and Amazon in the tablet space. The Associated Press takes a look at how the tie-up will make college textbooks a key component of its e-book strategy,  Mary Jo Foley wonders if a Windows-based B&N reader is in the works, and Om notes that the deal values the Nook business at substantially more than that of the bookseller itself. But Florian Mueller covers an under-reported aspect of the deal, noting that it eliminates one Android-related patent dispute and leaves Motorola Mobility as the only manufacturer of Android gadgets still entangled in litigation with Microsoft. Whether that’s good news or bad news for Motorola has yet to be determined.