Ok, so everybody with a Wii (in the USA) was given a copy of Wii Sports, so a review may seem a bit pointless. Of course, if you bought a Wii, there's a good chance a reason you did so was because of seeing Wii Sports in action. Some people may not have seen the game in action yet (like... um... the Amish?), so perhaps this review can help shed some light onto why the game has converted so many skeptics.
Simple, Yet Effective
The premise behind Wii Sports is simple - 5 simplified sports games that all take advantage of the Wii Remote in magnificent ways. You'd think that with the game being a launch title (and free) the motion sensing capabilities of each sport would be limited and/or clunky. For the most part, this couldn't be further from the truth. Bowling, Baseball, and Tennis are all incredibly fun and intuitive. Boxing and Golf do work pretty well, but unless the other three, they do require some getting used to.
Besides bowling, each game has some limitations. In baseball, you control only the pitching and batting while the fielding and base running is all handled for you. In tennis, you're only in control of hitting, so your little guys run all by themselves. Golf's mechanics are all there, though you're limited to 4 total clubs. With Boxing, you control the blocking, punching, and some movement, but you aren't able to really circle around.
Extras and Depth
Many have harped on the lack of depth in Wii Sports. Sure, you don't have any actual tournaments or leagues for any of the games so you won't get more than a single game of each at a time, but there are some subtle extras that do add more depth and replayability.
Each sport keeps track of your rating, a number that increases or decreases depending on how well you play. If you get to a certain level, you get "pro" status which grants some added bonuses (more fans in the stands, a different ball in bowling, etc.). This rating adds just enough incentive to keep you interested as you'll definitely be motivated to get pro status in all 5 sports. On top of that, it's something to brag about with your friends.
Besides the points system, the Wii Fitness Test and Wii Training options give you some fun little challenges in each sport - three per to be exact. You can do them individually during Wii Training, trying to get a gold medal in each or you can take the Wii Fitness test to see how good you can do with three random challenges thrown at you. I found the fitness test to be surprisingly addictive. For the few weeks I always made sure to do the test once a day to mark my improvement. Even after I could consistently get the best rating (20 years), I still found myself routinely turning on the Wii just to take the test.
More Than a Game
As cliche as it may be, Wii Sports really is more than just a game. It helps prove Nintendo's promise of a revolution in gaming. News stories have popped up everywhere about families all gathering around the system to play a round of tennis, or how the system is being taken to retirement homes so that some senior citizens can get in a round of bowling. The game truly does work on many levels for many different groups. Nintendo bundled the game with the system for a reason - it's pure, simple, fun.