Third-parties aren't going to waste their big franchises on the Wii. They're going to continue attacking the 360/PS3/PC as one platform, as that's what's going to give them the most sales and make them the most money. People seem to believe that this is the PS2 era or the PS1 era. It's not, and the Wii is not the PS2. Parity is at an all-time high right now; third-parties are taking advantage of that fact, and they will continue to do so. Right now, there's no reason for developers to use the Wii as their primary platform. Even if you're a Japanese developer, with the way the Japanese market is looking—dry, small and niche—your best bet would be the Nintendo DS.
Thus, we have seen most of those popular Japanese games on the DS instead of console (Like we use to see on the PS2). Wii fans should be happy with the third-party support they have, since there are some very good third-party games heading to the Wii. However, you're never going to have the same support the PS2 or PS1 got. There's way to much parity in the industry for that. If you're not happy with the Wii's support, there are other consoles out there you can buy.
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