So, I just got off the phone with Nintendo Customer Service.
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Basically, I told the lady I talked to, "Listen, with Smash coming out today, I've been reading Smashboards all day, and I don't know if you guys actively read that forum for feedback, but a lot of people are saying this, and I'd like to throw my support behind it: I'd pay you guys serious money for costume DLC for Smash, but especially the super cute costumes from the recent New 3DS commercials in Japan. I get that it's a Japanese commercial, so we'll never actually see it here in the US on TV, but still, I will pay you money, right now, for Toon Link in a green suit and top hat, and I know other people would, too."
Her response? "I'll pass this on to our marketing and product planning teams. And, I know that the planning team listens to feedback as much as they can, so if enough people feel the same way you do, I wouldn't be surprised to see them make that an actual thing you can buy in the future."
So, get on that, guys.
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Apparently, Nintendo Customer Service is starved for positive feedback calls, so if enough people ask nicely, we may actually get what we ask for.