The main public docs for Games For Windows cert can be found here http://msdn.microsoft.com/en-us/library/bb173456.aspx
I'm not 100% sure if cert questions for windows can be asked in public. I know for XBLA gamesMachaira is right but the windows world is a little more open.
However the certification process itself is controlled so when you get to that stage you will have an account manager to ask. Before then make your best guess based on the docs and you should be very close if/when you get to the final process.
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