Anyone that enjoys brainteasers will love the game. The pleasant story and atmosphere just makes it that much better.
The difficulty of the game is just right. Some of the puzzles are genuinely stumpers which can be solved with the use of the hints. Sometimes, though, the hints don't really do a very good job of highlighting how to solve the puzzle. Considering the only times I've bothered to use all 3 hints on any given puzzle I still failed to get the answer right on my first try, I'd have to say that it doesn't do quite what it should.
The mini-games (the hamster cage, the camera, etc.) are quite fun and a pleasant diversion from simply doing puzzles the whole time. I wish there were more of them, or that there was a greater reward than simply giving you easier access to more hint coins, but I had fun doing them in and of their own right and that counts for a lot.
Lastly, there's the presentation. Level-5 has always been very good with their artwork, cut-scenes, and overall plots. It's on the kiddy side, but it's still not quite adolescent so the adult mind won't feel like they are being asked to sacrifice brain-cells in order to get through the story.
I haven't played the first Layton title to comment on additional features this one might have over the original, but I'm fairly certain you, my reader, already know if you're the type of person that likes brainteaser puzzles. This game is highly recommended.