I would not recommend Motorstorm for a fast racer. Those games feel really slow to me.
I would recommend Burnout Paradise if you want a fast racer.
Get Call of Duty 4 or 5 or Resistance 2 if you want a great shooter. Otherwise it looks like you have the right idea in holding out for Killzone 2. That game looks to have lots of replay value. I played the beta and its really fun, but it definitely has a heavier, slower feel than most shooters. The guns feel like they have realistic weight and perhaps armor makes movements such as turning slower as well. It took a little getting used to but in the end it felt right and added to the physics when players ragdoll to their death. The bodies have weight to them as they crash into objects and fly through the air after a well timed grenade. Its awesome!!
Oh and dont miss Resident Evil 5 on March 13th either if you are a fan of action shooters.
