EDIT: After registering my games en masse, I'm up to 1020 Coins with Platinum status. Does that qualify me for the Mario badge set, or for the next reward? Is there a certain time at which new prizes are announced? If so, I might hold on to my Coins.
Elite status is based on the number of coins you earn in the year, whether you spend them or not, if that's what you're worried about.
I was afraid I wasn't going to make Platinum this year, but turns out I'd forgotten to register Diddy Kong Racing, Personal Trainer: Cooking, and HeartGold back when I got them, so between those coins, those surveys, and a couple surveys I still had kicking around, I'll just make it, without even having to buy all the DSiWare clocks at the last minute.
(I also forgot to register Meteos and Mario Hoops, but those don't count apparently. And the games I have that I forgot to register that would count (Mario Kart DS and Yoshi's Island DS), I don't know what I did with the codes from them. And I also lost the codes for Partners in Time and Super Princess Peach, which also wouldn't count, even though Super Princess Peach is in
this picture on the site and should totally count.)