While Blizzard could just alternate between spitting out StarCraft, Diablo, and WarCraft games until the end of time and keep themselves extremely well-fed, it looks like they're going to be branching out. They're developing a mystery project in addition to StarCraft II, Diablo III, and their next-gen MMO.

The Employment Opportunities page at Blizzard's website currently lists two open Software Engineer positions under the heading "Unannounced" (via DIII.net). Job listings for the next-gen MMO (name still unknown) are filed under "Next-Gen MMO" so the Software Engineer listings are for a completely different game. "This is your chance to get in on the ground floor of a dynamic and focused team working on a brand new project," states the job description for each opening.

IncGamera, citing an inside source at Blizzard, reports that this new project is not a WoW expansion or related to the next-gen MMO in any fashion. It's a brand new game which is using the WoW engine for testing purposes.

Unfortunately, that's all that was revealed through the source and while that information doesn't explain what kind of game it is, it does suggest that it's going to be something you've never seen from Blizzard before. It's a good opportunity for everyone to dust off their StarCraft Ghost rumor-mongering articles, too.