It takes a little getting used to, but since the goal of the game is to avoid some block types in the interest of maintaining combos, you're not really focused on trying to hit blocks to play the song, a concept some may be accustomed to from Guitar Hero or Rock Band. Instead, Audiosurf turns your song into a puzzle game, requiring twitch skills to hop between the game's three lines of blocks and snag the right colors and power-ups to create combos with the highest point yield.
And even though it looks like a racing game, it's not. You have no control over how fast your ship accelerates; that's all dependent on the song you choose. If it's a high tempo song, like drill and bass or something to that effect, expect a blisteringly quick and difficult ride. Sometimes vocals boost your speed, often times you'll speed and slow along with the drums, or sometimes a quick guitar riff will blast you forward. Even though the song will continue playing independently of what blocks are hit, their positioning often corresponds to bass echoes, guitar strums, and snare hits, so you do get, in a roundabout way, a sense that you're riding the song, as the game's tagline suggests. Then there's the track itself, which if you've loaded in the right kind of song, will undulate according to the rhythm.
The game didn't really click for me until I loaded up Jay-Z: Unplugged. With The Roots providing a solid, consistent beat, I got a much better sense of flow than with something like Faunts' M4 Pt. II (end theme from Mass Effect), a song filled with so much electronic distortion that it didn't serve as a particularly thrilling session of Audiosurfing.
Personally, I had a great time testing out Boards of Canada and Hot Chip, which translated to some standout experiences. Speaking of "testing out," one of this game's more meta side effects is it'll actually get you to go out and buy new albums specifically to try out in the game. I mean, why sit there at your desk browsing web pages while listening when you could actually be playing the new songs? I'm sure music purists would scoff at the notion, but it's nevertheless one of the game's draws.
