Just got done playing through the first boss. It's definitely the best Sonic I've played in a while (post-Genesis), but I'm far from giving my final verdict. The "cheap deaths" I've heard professional reviewers claim aren't cheap; there's even a little hazard sign that pops up when you're near a bottomless hole.
The controls could be tighter, and I think a better tutorial would've helped. There's a tutorial giving help when you ask for it, but it leaves me confused with explanations that say "use the boost button"--okay, which is the boost button?! The manual kind of tells you, but the format could be easier to understand.
Anyway, I've found that I like the Classic Controller/Pro over the GameCube and the Nunchuk combination, but I haven't used the Wii remote sideways yet.
I'm a little disappointed by the game's stiff and unbalanced controls. They feel kind of sluggish, especially when moving slowly. The lack of Sonic's "spin-dash" is baffling, yet they gave him a wonky power slide that he can just slide around with everywhere. Sonic is not supposed to slide; he rolls up into a ball - weird design choice. Additionally, the level of play required is highly uneven - Some levels practically play themselves while others require precise effort. It's very jarring. About the only thing I really like are the visuals - nice work there, especially for a Wii game.
The controls definitely took me a while to get a hang of. But, like I said, I like the Classic Controller/Pro's layout, so I played a little bit more last night. I already forgot the controls the first few minutes, but then quickly readjusted and it was smooth sailing. I keep forgetting to follow certain onscreen commands, but other than than, I really look forward to playing the game.