Sonic Colours? I barely Sonic know hers!
Sonic Team really nailed the concept this time around. Sure, the daytime Sonic Unleashed levels were fun, but there were like about 8 of them and you had to navigate a menu for 20 minutes just to find them. In Sonic Colours, every aspect of the gameplay has been streamlined for the enjoyment of the player- loads of "daytime" style levels with stellar design, great gameplay mechanics (including the titular wisp "colours") and let's not forget some of the best Sonic game music since Sonic 3's funky marble garden zone.
Above all else, what I really appreciated with this game was that you could just start it up and play through the levels continuously (in challenge mode) just like the old Sonics- no gimmicks, no mini-games, no sidetracking, just core gameplay from start to finish- be it 2D or 3D.