Another month has gone by, and in the world of video games, the story remains the same. I have been very impressed with the resilience of the Nintendo (OTC: NTDOY) franchise. This Wii "fad" just continues on and on. According to data from marketing-research firm The NPD Group, last month, the Wii system sold over 714,000 units, and the Nintendo DS moved over 414,000 units. Game systems by Sony (NYSE: SNE) and Microsoft (NASDAQ: MSFT) were left far, far in the dust. The Associated Press said all other major systems couldn't even reach 200,000 in terms of unit sales.

And now, this week will bring a potentially big catalyst for the Wii. The Wii Fit device, which is an electronic exercise program designed to take full advantage of every innovative nuance offered by the console, is expected to be a huge hit. I can almost guarantee that it will be, as I personally have heard a lot of buzz over it and, on an anecdotal level, I know a lot of people intend to pick it up when it is released. I don't think it's going to fail, even at the relatively high price point of around $90.

I'm not, however, going to buy any Nintendo stock based on the coming excitement this week, even though I think the shares have a great chance of popping. I've owned Nintendo in the past and made money on it, and I'm always thinking about when to re-enter, but for now, I am staying on the sidelines. For me, it feels like too much of a risk in terms of investors selling on the news once the Wii Fit is out. I could be wrong, of course; in fact, Nintendo's ADR's closed up a buck to settle at $72.50 per share on Friday. That puts it not too far away from the 52-week high. But, as much as I love the video-game sector -- I own shares of Activision (NASDAQ: ATVI), in fact -- and as much I recognize Nintendo's dominance over the PlayStation 3 and the Xbox 360, I'm going to sit this one out.

Disclosure: I owns shares of Activision; positions can change at any time.