I personally hate the Gamecube. I liked Nintendo's stuff right up until the 64, and that's when I stopped. Gamecube had some ok games on its launch but any of them are incredibly annoying or downright childish. Last time I checked, Super Smash Bros Melee is STILL on the Top 10, a sign that the system hasn't had too many great games out recently.
People get on my nerves when they harp about RPGs and that crap, and I don't mind them until they start shoving their bullcrap on ME. Then I get pissed off, and the Gamecube seems to be an RPG and kid game repository (and so does the PS2). Half the stuff out is either Zelda, Mario, or Pokemon. The other half is stuff out for other systems. Gamecube doesnt have enough original console-only games to spark my interest.
I think GameStop's eye-gouging trade in rate of $30.00 speaks too.