Rob Kay, design director at Harmonix, told CVG during an interview:
"Come on Nintendo, we need a hard drive. That’s what we want. The whole problem is there’s nowhere to store it. If the platform could do it, we’d jump on it. It’s something that we championed to Nintendo, that we’d like to do it. Who knows what will happen down the line, I don’t know what’s coming down the line, but that’s the reason there’s no DLC in Wii Rock Band"
This call is, of course, made on behalf of all the Wii gamers that are to miss on the downloadable content. Sarcasm aside, Harmonix sold over six million songs to PlayStation 3 and Xbox 360 users, so basically it’s once again a “all about the money” situation.
Harmonix could very well beef up the original game’s song library or allow gamers to use SD cards to store the songs, but apparently such options are not on their agenda.
As for Nintendo, the company stated over and over again that the release of an external drive for the console was not something most gamers would willing to go for, so the project remains buried, at least for now.