So why should anyone care about the PS3? The zealots who got them got them already, and all the rest are just not gonna care, get a Wii (gameplay) or get an XBox (more games and similar "oohh, shiny" graphics)
For some, it's a case where we're assuming (maybe foolishly) that the PS3 will eventually have some interesting and unique games that are otherwise unavailable on any of the other platforms. Examples of this for the PS2 for me would be Ico, Shadow of the Colossus, Ratchet and Clank, etc.
It's akin to asking why anyone bothered buying an original XBox, when there were so many more titles for the PS2? If you were a Halo fan, the answer was obvious.