A fairly long list of positions to be filled has popped up at the Microsoft Careers site; specifically, 24 Halo-related jobs are open with 343 Industries, the team responsible for the Halo Waypoint and any future Halo games that Microsoft wishes to publish.
What does this mean to Co-Optimus? Well, aside from the obligatory "go get 'em!" to anyone who wants to pursue a career with 343 Industries...this also points to a new co-op outing in the Halo universe. The franchise being what it is, we'd put our money on co-op being included in whatever these guys are cooking up. We'll keep our eyes open for you, and our VISR on.
Source: Microsoft-careers.com