My wife gave me Nintendo's Wii Fit for my birthday last month. It has been a lot of fun and a surprisingly good workout, once I got over the embarrassment of a) needing something to make me exercise, and b) that thing being a game.
I've been using it for a solid three weeks now, four or five times a week, 40 to 50 minutes at a time and find that it truly is a decent workout. (Grain of salt time – my definition of a good workout means I get sweaty, tired, and have sore muscles the next day.)
One of the things that has made it the most helpful to me is that it is right downstairs in my living room. In other words, I don't have to leave my house. (For the record, it's not that I'm so lazy, although I am, it's that I've worked really hard at making my house an extremely comfortable, pleasant place for me to be and I am loathe to leave it.) I can get up in the morning and get in a workout while the coffee is brewing. Then it's breakfast and a shower and then, well, usually back to bed if I'm being honest.
Another positive aspect is that the onscreen coaches and measurements let you know if you're doing something well or not. Specifically, on the yoga exercises, being able to see where you should be shifting your center of balance to, and how much force you should be applying to the Wii Board is very useful.
However, I find that while I enjoy the workout, it's not really enough. In other words, it is a good supplement to regular exercise, but I (at least) still find that I have to spend some time at the pool or going for a walk to feel like I've had enough exercise for the day.
And it's a bit expensive.
But overall, I have enjoyed having the unit and plan to continue using it. It's the kind of thing that, for more active people, people who have no trouble getting to the gym, it might be nothing more than a toy. For people like me, however, sedentary and more inclined to video games than physical activity, the Wii Fit system is a great tool to help fight obesity.