Machinarium is hands-down, the best game I have played in a decade. I just finished it a couple days ago, and I am seriously jonesing for more of the same -- I'd already played Samorost 1/2. Although the soundtrack is the perfect atmospheric accompaniment to Machinarium, the fact that an "improved" version is sold with the game is a testament to its high quality. In terms of difficulty, I'd say that they're a bit easier than the puzzles in the original Myst or Riven. I enjoyed Machinarium more than Myst in part because I could survey each scene without losing my orientation in first-person navigation.