When I play the Wii, it feels no different to me than using a standard controller. Obviously it's a different control method, but the end result feels exactly the same, like taking two different routes but arriving at the same destination. The Wiimote can often frustrate me, especially in Wii sports where the detachment and lack of impact hits hardest. So inevitably, to me the Wii feels like a Gamecube with an online service. Especially since the games are not at all different to what we already have. Zelda, Mario, Sonic, Rayman, Red Steel... Some are decent, but not in any way innovative. What about such Playstation classics as Katamari, Loco Roco and Vib Ribbon? All are far more inventive, and need only a standard controller. The PS2 was the best console for innovation and quirkiness, if there was one, for the last generation, while the PS3 already has oddities like Flow and Super Rub a Dub.
I'll admit to being a massive physics *****, but I enjoy freedom in games. Being able to bring down buildings realistically by shooting away sections of wall, with bricks, wood and metal bending and breaking due to the physics engine, not what developers have to program in manually, is the sort of thing that has huge potential and that interests me the most. The Wii will never provide that for me. It will provide Smash Bros though, so I will be making a lot of use of my housemate's Wii when it arrives.
And fimbles, I could get a PS3 for £380 right now. Still expensive, but a lot better than before.