Yea, I'm not sure where this petition is coming from either. I just checked the gamestop website where I have my reserve and it says $59.99 USD, which is what every other ps3 full retail game has been releasing at since the dawn of ps3. Which is what you'll pay for batman, assassin's creed 2, uncharted 2, bioshock 2, MAG, and pretty much any other game you're looking forward to. Can't afford it? Rent it. Deal with it.
If you do want a cheaper game though, check out Mini Ninjas, it looks like it might be pretty fun, and for some reason is priced at $49.99 USD. Yay,,, just like back when I owned a ps2.