My wife and I just bought a Wii a couple of weeks ago and, in spite of us both working full time, we are still clocking up about 5 hours of play-time every day. It is a fantastic console and a lot of fun to play.
And, it connects easily to my Airport Express, meaning I can email, surf the web and trade Miis with other people.
The controller is a technological masterpiece: it contains a rumbler, a speaker (awesome for multiplayer party games like bowling or billiards, as it lets people know when it is their turn) an accurate optical tracker and a number of accelerometers and position sensors, all connected by bluetooth, and it also contains memory and will easily sync with other Wiis - which means your Mii and your save games can go with you if you visit a friend. The console can take up to 16 controllers.
Memory is expandable via SD card. The web browser is far from finished (it doesn't even have an address bar!) but does work well with sites like Flickr, YouTube, and so on.
If you can get your hands on one, the Wii is a wonderfully fun games machine at a bargain price.