Starting to narow down the field as to which ecm to upgrade to. I'd like to fit a nitrous kit down the track (maybe twelve months away) and am assuming that it would need to be in conjunction with the ecm. Is this correct? Which ecms cater for nitrous? Power commander v has an optional external switch gizmo to switch between two different fuel maps, could that be used?

What year and model are you going to be running. Your still going to need to control the added NOS and fuel from the outside if you plan to add much NOS to the bike. The stock Delphi EFI controller will handle it much better than an other ECM on the market today.