I found FEZ to be a very charming game. It doesn't do many of the things similar-looking games do, but it does its own thing nicely.
Its main mechanic is how the world is the two-dimensional projection of a three-dimensional space, which you can - and have to - constantly rotate in order to traverse the projection of another side.
The platforming is fairly trite - the rotation mechanic is used very cleverly, but there's just lots of waiting for the slow protagonist to walk somewhere. Also, surviving a fall usually makes you lose more progress than dying, which is very annoying.
The game world is lovingly designed, however. The relaxing, beautiful and mysterious atmosphere will make you smile and the dragged-out platforming actually helps you take in the details.
There's cryptic clues scattered everywhere, deciphering which requires attention to vastly different things and is one of the main attractions of Fez, though you may play through all the way without understanding any of them.
I recommend this game for its beautiful ambience and strange puzzles that may please fans of games like La-Mulana and Antichamber. Be aware of its slow pace and focus on atmosphere over action though.