It depends...
It's gathering more dust than my PS3, PC or iMac, but not nearly as much as my X360. Though to be fair, I hardly play any games on my PC or iMac, so it kind of depends if you count "work" as "gathering dust".
I've used my Wii for Xenoblade Chronicles, The Last Story and Pandora's Tower. MadWorld and No More Heroes 1 & 2 as well, but I never finished them. (Nice concepts, but the execution wasn't entertaining enough to keep me interested beyond the halfway point.) But, nonetheless, the first three titles I mentioned have kept me somewhat occupied and I still fire 'em up sometimes (you know, to get that 100%).
I also have New Super Mario Bros. Wii, but never finished that either - I don't need to play some Super Mario World meets Super Mario Bros. 3 re-hash if I can just play either of those original games. Same for Super Mario Galaxy, for a game than got nothing but 10s and the occasional 9, I was severely disappointed. Same with Zelda: Twilight Princess. I don't care if Okami copy/pasted its formula from the Zelda series, at least they finally did something else than repackaging Ocarina of Time and selling it as a new game. God, I've started ranting, time to wrap it up.