I just completed it. For me, from level 20 and on, the game became very slow, and therefore tedious and hard to enjoy. However, the first 19 levels were very enjoyable, and made good use of the new tools that were introduced. Unfortunately, it didn't really have that Winter game feel that Nitrome always brings to these games. So therefore, this sits as my least favorite Winter game. Other than that, I liked the surprise Nitrome gave us in the last 10 levels.
So, what did you think of the game?