18 months would have the 360 successor (the 720?) on store shelves in February 2014 at the latest. Analysts seem to think that a late 2013 release is more likely; this is entirely within the realm of possibility as the job listing specifically said "over the next 18 months," meaning sometime within that time frame
"Over the next eighteen months, Microsoft will release new versions of all of our most significant products including Windows (Client, Server, Phone and Azure), Office, and Xbox, along with completely new offerings like Microsoft Surface..."
When questioned, a Microsoft employee released the following statement: "Microsoft is always looking for talented people to innovate now and in the future. We don't have any further comment on this or any other job posting."
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