You already have to list each pistol/revolver you own or co-own on your license, and you already have to inform your county pistol permit office of any changes in your address. So the only difference is that the information is being collected in a state database every 5-years. I believe each county transits all information to the state as it is received anyway.
I think it is more likely going to be used to impose a state re-registration fee in the future to raise more funds for the illegal alien legal defense program Cuomo wants to operate.