Pretty nice game in general!
The mechanics are pretty basic modern platformer mechanics, with regular jumps, wall jumps, and a series of different obstacles, but the game utilizes them pretty well. First of all, because every platforming section is carefully made to be challenging (even frustrating at times) but never in an unfair way (that is, the mechanics are consistent, nothing catches you by surprise, and trial-and-error is kept to a minimum). A few parts are really, really unforgiving, but never unfair.
Another very interesting thing is how we can see a lot of the playing field at once, by virtue of the tiny sprite. That, for some reason, gives us an awesome perspective of just how huge an endeavor is ahead of our little square friend, making us all the more satisfied when we finally finish climbing that gargantuan tower.
Other than the gameplay, there's also the song that plays throughout the game, and it is pretty awesome. It kept me pumped from beginning to end, being appropriately epic while still evoking a bit of a Christmas spirit with the typical bells. It loops a bit strangely (it sounds like it stops for a fraction of a second before looping), but that didn't bother me too much.
The graphics are basic, but they do their job, and there's something appealing about a game where we can see so much at once, even if the single elements of the thing we're looking at are all basic.
So yeah, definitely give this a try. It's not perfect, though, and it can get frustrating.