Destructoid has an article up reviewing Cooking Mama: Cook Off for the Wii, which you can read at the link below. However, the most important tidbit seems to be the information regarding why the game has no online multiplayer. See for yourself:

My biggest bone to pick with the game is the lack of online multiplayer. I spoke with the Majesco rep about it and he wasn’t too pleased with how Nintendo was still keeping their online service a secret from developers. Basically saying that Nintendo is not letting devs know how to develop their games for Nintendo’s online service.

In case you don’t think this is a problem, let me tell you, it is. In fact, the rep was telling me that the online question is the #1 thing he is asked all the time about the game. Everyone wants it and everyone wants to know about it. The bottomline is that for now, if a Wii game doesn’t have online, don’t blame the developer or publisher. It seems that Nintendo is content to keep online on their games only … for now.

Nintendo’s holding something back that they don’t even want developers to know yet. Is it just not ready? Or is there something big on the horizon? We know it’s almost an unconfirmed certainty they’re working on new channels, new aspects for the Wii Shop, but what about actual online play?

Destructoid