I think we all knew when the Nintendo Wii U was unveiled back at E3 that other next gen consoles would be coming too. It's also safe to say that shortly after one version of a game console launches, the next is being worked on. When some workers at Microsoft hint they are working on the next Xbox, take it with a grain of salt. They probably could have said they were working in it years ago.
Over the last several months were have heard a few rumors that Microsoft was at work on the Xbox 720. This is the first "confirmation" from someone claiming to work on the project that another console is coming. The tip comes from the resume pages of some Microsoft workers on LinkedIn. I guess someone didn’t think about what they were writing on the resume thoroughly.
The tips come from the resumes of Jonathan Harris, the Senior Creative Director for Xbox, Patrick Corrigan that says he does groundwork integration for Xbox, and Joe Langevin, an Xbox hardware intern working on high-speed data buses in next gen devices. All cite work on next generation console on the resume.