Microsoft&39's Office for Mac 2011 is being featured as one of the headlining downloads in Amazon&39's new Mac software store.

Despite being in the middle of litigation with Apple over the use of the term "Appstore" for its mobile application store, Amazon today launched two digital downloads stores for Mac software.

The new stores, picked up by The Loop, cover games and applications. Altogether, Amazon's got 252 pieces of software up for sale, the majority of which are applications versus game titles.

Just like Apple's Mac App Store, which is how the company sells both its own and third-party Mac software, Amazon users can redownload applications if they somehow misplace the file. However, unlike with Apple's offering, there's no mechanism to keep applications up to date--something Amazon has left up to software makers. Some applications are also bundled with DRM or serial number authentication, the latter of which is not a concern on the Mac App Store.

So far there's already a handful of software that cannot be found on the Mac App Store, including Microsoft's Office for Mac 2011, which is being promoted heavily. Microsoft has long offered it as a digital download through its own store, but not on Apple's Mac App Store.

As part of the store launch, Amazon is offering buyers a $5 discount on any Mac game or software purchase through June 1, 2011.