Once Nintendo gets moving on the online multiplayer market I'll most likely pick up a wii. My dad keeps asking about it, and it's definitly something that I could get my Dad, Mom and Sister all playing.
Other than that as of now it doesn't seem to be a great investment as far as games come. There are like two or three games out that I'd want. I want to see a Top Spin, a Table Tennis, an MLB game, I mean Wii sports is fun but it gets old after a while, and it's always nice to actually use some of the graphics power.
And of course, as I was typing this I realized that my Dad is at Costco now and its a high possibilitly that my sister might convince him to buy a Wii, if they've got some in stock.