Could this mean that there's a Halo MMO in the works?
Instead, it looks like the developer's prepping to go right back at it. Recently, Microsoft put out a call for software engineers to join the Halo Game Services team, which is "working on building the next generation of backend services to power Halo 4 and our new game saga. We also build the greater Halo Universe - services on console, web, and mobile through Halo Waypoint." The ideal candidate is described to have "Experience in MMO development."
It's no surprise that Halo 5 is already in incubation. However, the fact that Microsoft and 343 are hiring for developers with MMO experience could possibly mean that another Halo MMORPG is in the works.
The previous Halo MMO project, worked on by Ensemble Studios, was cancelled long before anything really concrete came into fruition.
Still, with the MMO market being competitive as it is, with many key players transitioning to free-to-play to match Asian markets, it seems an unlikely time for Microsoft to want to make an entry into the genre. Then again, a Halo MMO could just be the thing that helps shake up the market.
For now, Halo fans will just have to be contented with the fact that 343 and Microsoft are already hard at work with the next entry in the series.