I was just reading the wiki page on this game and basically what it said you should expect from this game is;
Firstly the gameplay is quite similar to the previous installment Sonic Unleashed with that 3D-2D style (the camera will shift to a 2D plane at some stage in the level) which you know I found refreshing in Unleashed because it brought back those early childhood memories on the original Sonic games..
Secondly you should look out for wisps which allow you to traverse from each level, each wisp has a colour to it which I guess is where the colours theme partly comes from..
All in all this game should be sufficient until SEGA releases Sonic The Hedgehog 4 – Episode 1 which by the looks of it we in New Zealand wont be getting until next year.