Like some of you elaborated, there's a variety of reasons for the shunning of the Wii, from the ridiculous, to the relevant.
For me, it's because it has last-gen graphics, and very few games that interest me - all the wii sports, resort, party babiez, whatever, is pointless - as in, I have zero interest in that stuff. I grew up, thus I couldn't care less about Mario, specially if it's a kart game, sports game, washing-your-teeth-with-Mario game, i've always found Zelda completely overrated, and the third parties, for the most part, are crap on the Wii.
That leaves Metroid Prime 3, No More Heroes and Madworld as the only Wii games that interest me. One of those is coming to 360/PS3 with much better graphics (NMH) now, and i'm not gonna buy a console for just 2 games.
Essay Pro