Yeah, I like my beefed up Gamecube...
...then again I liked my regular Gamecube.
I recently had my tenant's PS3 hooked up to my 1080i 50" DLP TV and played several games. The graphics were impressive for a minute, then you actually have to play the game using a traditional controller and you forget about the graphics completely. I played Fear, Resistance:FoM, Motorstorm & GT-HD. I tried Motorstorm with tilt steering and that aspect worked like the Wii. However playing the 2 FPS games was a chore compared to even a so-so FPS on the Wii (Red Steel).
The Wii's controls is what makes it "Next-Gen". Until you've put in some hours with them you don't know how bad tradtional controls were. I own RE4:Wii and GC editions and the improvements over the GC version (faster load times, 75% more pixels <852x480 vs. 640x360>, better lighting and particle/fog effects) are enough to see there is much untapped potential in the Wii that a quick port by a competent developer fleshed out. Included in the disc is a trailer for Resident Evil:Umbrella Chronicles - an arcade shooter like VirtuaCop. The game looks graphically impressive. It's almost FMV quality but it's totally rendered because you can look around in this on-rails shooter to find hidden bonuses. Again - a good developer can do wonders with the system.
Poor Wii graphics to date are due to lazy developers (who didn't even approach Gamecube-level graphics) and the fact that first batch of Wii games didn't use the finalized gpu api and documentation. They were working with tweaked Gamecube specs.