Sadly, the Japanese release of Guitar Hero 3 went over about as well as the concept of racial equality here, so I'm going to have to import if I want Aerosmith. 
I'm going to take a wild guess and say that GH3's failure here was due to Activision's absolute piss poor localization.
First off, you're competing against GFDM, which is a well-established series in Japan and has music that appeals to the Japanese people. So, to compete, you bring a game full of (older) American rock tracks that will only appeal to a very niche group! Then, don't bother with translating anything, just keep all the menus and content in English except for the training area. Then, for marketing, just use the American TV ads (complete with English voiceovers) and lazily paste some Japanese information on the last few seconds of it. Don't bother with any store displays or big print ads. Oh, and to top it off, don't even try to localize the title. Just keep it at Guitar Hero 3, despite the fact that the first two games never came out in Japan. This will ensure that any non-hardcore players will be confused about the series!
Bloody morons, this game deserved to fail here. It would be like Konami bringing GFDM to the States, only translating the tutorial, and expecting it to sell with a songlist full of Japanese songs and menus full of Japanese text. Sure, a small hardcore fanbase will buy it, but you're crazy if you expect it to have anything that resembles mainstream appeal. At least Konami has the sense to change the game up substantially for Rock Revolution.