It's Resistance: The Fall of Man.
Also, it's worth it to YOU because YOU have the money, Mr. I upgrade-everytime-new hardware-comes-out.
For the average consumer like most of us here, no it's actually not worth it. The PS3 launch lineup is crap. Resistance is the only good game they have. All the other games are on the Xbox 360 and some even look better on the Xbox 360. I'll wait until Metal Gear Solid 4 and some other games come out before the $600 price tag can justify itself.
Then again, most of the PS3's games are coming to the Xbox 360 anyways. Armored Core 4 and Virtua Fighter 5 are no longer PS3 exclusives. Metal Gear Solid 4 was rumored to be on the Xbox 360, but Konami has announced it'll remain PS3 exclusive for now. Don't count on it...Metal Gear Solid 3 was eventually ported over to the Xbox and same for the Grand Theft Auto series. Konami can't justify spending so much money on one console that hasn't even sold 1 million units, so I bet it'll come to the Xbox 360, even if it's after the PS3 release.
Heh, I'll add this for the hell of it.
To be honest, if I had to choose between the PS3 and Wii, I would choose the Wii hands down. Why? Fun, innovative, cheap and kickass games. Just The Legend of Zelda: Twilight Princess alone is a good enough game to justify a Wii purchase. Can Resistance do the same with the PS3? Nope.