Without expanding its appeal, the Xbox 360's sales are likely to top out at the same level as the Xbox - just over the 20 million mark, compared to 118 million and counting for the PS2.
This is the challenge which faces Moore's successor, Don Mattrick - and we don't think that it's any coincidence that Mattrick is resolutely a "software guy", having previously served as president of EA's worldwide studios.
The launch year of a console and the build-up to launch is all about hardware, and Peter Moore was the finest launch period executive Microsoft could have hoped for. However, 18 months in, the focus needs to be unrelentingly on software - and that, hopefully, is what Mattrick will bring to the mix.
Moore's tenure at Microsoft has seen the Xbox transition from being a plucky but frequently misguided newcomer in the console market to being a front-runner in the next generation race.
He leaves the business with enormous challenges still facing it. But the very fact that Microsoft is not only still in the console business, but is actually a strong contender in that business, is Moore's legacy.