Only vaguely. Amplitude is the sequel to Frequency, which was a sleeper hit for the PS2. Those two and DDR all fall into the currently-popular genre of "rhythm-action" games, which can be described as increasingly-sophisticated musical variations of Simon. <a href="http://psx.ign.com/articles/150/150490p1.html">Parappa the Rapper</a> on the PS1 was probably the breakthrough title for the genre (in America, at least). The Bemani series (DDR, Beatmania, guitar games, etc.) has sold like hotcakes in Japan.
Whereas <a href="http://psx.ign.com/articles/161/161525p1.html">DDR and its many remixes</a> are based around physical dexterity (stomping pads to the beat), Frequency and Amplitude are centered more closely around the music itself, tearing it apart and remixing it through controller manipulation.
<a href="http://ps2.ign.com/articles/166/166450p1.html">A glowing review of Frequency</a>
I have Frequency, and don't quite "get it," but do regard it as an extremely interesting conceptual design.
<a href="http://ps2.ign.com/articles/166/166546p1.html">Rez</a>, on the other hand, is a shoot-em-up on rails (think Panzer Dragoon, Starblade, Starfox, etc.) that's designed around some serious eye-and-ear candy. EVERYTHING in the game (shots, explosions, changes in terrain, you name it) is kept in time with the techno beat of the background music. It's a maddeningly subtle concept that's well worth checking out and experimenting with, with different styles of play capable of unlocking all sorts of strange effects.
The Japanese version is coupled with a small vibrating device that plugs into the controller port, which throbs in time with the pulse of the game. Those of you with perverse applications in mind for said device can rest assured that you're not the first. Many have reported that it's the first game that their girlfriends WANT them to play.