Aiight, I got it figured out, there are three echelons (levels) of Wii graphics. Every game fits one of these three categories on the Wii.

So, without further ado..

Echelon 3 is the lowest level of Wii graphics. This is the bulk of games that simply look like GameCube games. Generally they look like impressive looking GC games, but GC games nonetheless. Examples:
1. Sponge Bob
2. Necro Nesia
3. Excite Truck

Echelon 2 is where most of the popular Wii titles live. They look like high-end GC games PLUS an extra bucket of light blooming dumped on top. They push the boundaries ever so slightly, displaying graphics that are out of GameCube's reach, but not by much. Examples:
1. Metroid Prime 3
2. Red Steel (getting close to echelon1 in new screenshots)
3. Project H.A.M.M.E.R.
4. Smash Bros. Brawl

Echelon 1 is a lonely place to live for a game right now, but hopefully that will soon change. This is the level of graphical quality that truly looks next gen, and beautiful, and is clearly well beyond what GC can do. This echelon is where games have huge draw distances, lots of bump mapping, clever lighting, high polygon counts, and generally impress the eyes. Examples:
1. Super Mario Galaxy