http://www.eurogamer.net/articles/the-colour-of-sonic-interview?page=1
"Eurogamer: Is Sonic Colours a reaction to criticism of Sonic Unleashed?
Takashi Iizuka: Yes. The team deliberately looked into the daylight stages of Sonic Unleashed.
After the release of that game the team had a lot of good feedback, particularly of the daylight stages. That's how the project initially started - focusing on the good side of the previous project."
Here's the entire topic
http://mynintendonews.com/2010/08/02/nintendo-sonic-team-blames-fans-for-negative-perception-of-recent-sonic-games/
"But how do the negative comments make you feel? Do you ignore them?
Takashi Iizuka: It's more that those fans are not positive towards the recent 3D Sonic games because we've been releasing only 3D Sonic games in the past couple of years.
It's hard to please both 2D and 3D fans at the same time, in the same title for instance.
This is why the team decided to release two different types of Sonic games. It's always hard to dodge every negative perception or make everybody happy with just one title. So we're giving two options to the users."
Hahahahahaha