After finishing it I don't think the game ended up being that good. There was really only 1 full sized level in the game just like the first one, then there were a few medium sized levels (Zoo, School), and finally a bunch of tiny levels (Snow, Fire, Hansel, Fireflies, Flowers, Water, Race). It didn't really feel any longer or more varied than the original by the end IMO. At first it seemed like it was going for a very different take with interesting objectives (Fire,Sumo,Snow), but after about 50% into the game all the levels just turned into the same get big or get x number of items. The time attack versions of the stages don't really do much either as not only are you just competing against yourself, but the stages are ridiculously short often ending in 1min or so.
The music was weaker and felt more repetitive, and while the story idea is hilarious the "oh no no no [YOU ARE AWESOME KING] yes yes yes" dialogue loses it's funny after the 10th+ time.
Then some of the stages had wierd issues. Like the 1st part of the cloud stage forces the camera under you and it's really hard to see or judge sizes; the racing controls were kinda iffy IMO.
Its a solid game, but I just feel disappointed that they didn't do more. I mean the snow idea was really smart...so why limit it to a single extremely tiny level? Same thing with some of the other one shots like the underwater level. I would've liked to have seen more of this interesting levels near the end rather than just getting bigger. The game rather than feeling like something special, feels like a retread by the end. I mean the last actual game level (not the final final level bit) seems almost identical to the last actual game level of the original. Since they already introduced the underwater gameplay, why not start the final huge level from the bottom of the ocean? The areas are a little different this time around on the final level, but it's mainly the same and feels disappointing (aka, I've already done this before). 25% into this game I was enjoying it; 50% into the game I was loving it completely, 75% into the game I was getting bored, 100% into the game I was ready to shelve it and move on.
IMHO it's worth it at the discount price they sell it for, but I would've felt a bit burned if this had been a full price game. I'd put the original at a solid A rating, but the sequel is closer to a B.