Education publisher Pearson has bought its way into the Nook Media joint venture between Barnes & Noble and Microsoft. The JV includes the production of Nook ereaders and tablets, and the operation of the Nook digital media store, and college bookstores. Pearson  spent $90 million for a 5 percent stake in the Nook Media, with an option to acquire up to 10 percent at a later date. [Source: VentureBeat]