Rise of the Planet of the Apps

This article from The Motley Fool gets into how the MicroSoft (MS) software landscape could change with the launch of a Windows 8 App store.  Two points that I hadn't considered (mostly because I don't think about MS much) are that MS products are mostly sold through middlemen, where Apple and Android are mostly sold direct, and, there are lots of pirate copies of MS software out there -article says it's estimated that 30% of Windows XP installs are pirated.  If an App store for MS could allow them to cut out the middleman and curtail piracy, they could charge a little less -making their products more competitive, and offer that all-in-one experience that makes Apple feel so easy to deal with.
Do we need another App platform/store?  Capitalism would say yes -competition increases innovation and decreases price.  Can MS make a go at this competition?  A large percent (article says 85%) of the worlds computers run windows of some flavor and if they could leverage this ubiquity correctly with a user friendly strategy they probably could.