Incipio is beginning its rollout of cases for the third-generation iPad with Lexington ($40), a simple folio that's available now in limited color options. Comprised of a hard matte plastic shell covered in faux leather, the latter material wraps around to form a front cover as well. We're happy to see that this case offers full edge protection, unlike some of the iPad 2 cases we've previously reviewed from this company. The tab and buckle system…