Your not going to get the graphical flare, or processing power of a PS3 or an xbo360. You wont get DVD playback or multimedia features.
But what you get is a dedicated gaming machine, with original Nintendo games.
And the wii remote really is fun and easy to use, and its no bad thing to use a bit of exercise to play a game.
I got one this xmas, and im impressed. Its great for parties and you get two games free with it anyway.
Its also nice to have a choice in games which ARENT just shoot, shoot, shoot. I love my PS3 for games like COD and Borderlands. But its nice to just pick a nice platform game like Mario up and chill out.
At the price, you cant complain. Its far cheaper then an xbox360 and PS3 and smaller. It fits nicely into the corner of the room.