There's a reason we don't compare Nintendo's little white fun machine directly to the PS3 and Xbox 360: there really is no comparison. In ways that are both good and bad.
The Wii is not really a next-generation game console, in the sense that it doesn't feature snazzy high-definition graphics or advanced surround sound, doesn't play movies and doesn't put much emphasis on online games.
What it does have are the exclusive Nintendo franchises, specialized peripherals like the Wii Fit balance board and, of course, that waggly little Wii Remote for arms-a-waving gaming.
Basically, you already know if you want a Wii. In fact, the thing has sold so well, you probably already have one. But versus the other two hi-tech game consoles, it's apples and oranges.
No offence, Mario.