In my humble opinion, two nearly perfect games in 21:st century have been so far: "Black Mirror" and "Nibiru - The Age Of Secrets". The thing worth mentioning is that they're both developed by "Unknown identity". They really charmingly brought in my mind the "Broken Sword 1 and 2". Those two dragged me into adventure games and I really love their atmosphere and interface!
(The third game is coming up from "Unknown identity" holds the name "9 Till Death" and because both earlier games banged me totally, I'm definitely waiting for that game! Also "Reprobates" is worth a look, because it's developed by "Future games", that was a publisher of both "Black Mirror" and "Nibiru")
I think that graphics are if not the most important feature in adventre game, then definitely one of the most important. And I don't mean, that it's the question of resolution or colour depth or anything like that techical part. I mean that graphics are important in a certain different way: They are the game world. They have to be inspirely drawn/made and they have to be good, so that the game has any chance to be good. In other words: There's two graphical meters: Technical quality and atmospheric quality. Please let's not mix these things up.
The reason for those two games to be the best in 21:st century so far is that their graphical outlet is simply very atmospheric and beautiful, puzzles are nice, story is charming and main characters are interesting. Also the gameworld is rich in details, (which is not the thing to say for example about "Syberia" or "Still Life", they're simply boring, cause you can look nearly nothing, it's all background.) Very good voice-acting and well-written dialogue.
