I'll take a stab. 2002 210.8(A)(6) Says GFI protection is required in
Kitchens -- where the receptacles are installed to serve the countertop surfaces.
So I think that would most likely mean no. However, I think it would be better to use a GFI if the outlet is readily accessible or the microwave is near a sink even if it is not required.
I don't think it matters if you use a single or duplex outlet in a kitchen, however the exceptions for basements and garages do make a distinction, so it would probably be better to use a single outlet.
