Jason, unfortunately you've got a problem fairly common to the laser-cut keys and their ever-so-tight tolorences. A bit of wear on them and the waffers within the ignition cylinder bind.

If a new key doesn't fix the problem, you'll have to remove the cylinder.

To remove it you have to remove the top and bottom plastic covers immideately behind the steering wheel (couple or four screws each). You'll then see a small (size of your smallest drill bit) hole above where the cylinder slides into the steering assembly. With the key in the accessory position, push in a small nail or drill bit into this tiny hole, all the while pulling on the cylinder.

If you're unlucky enough to not be able to turn the key because of wrecked waffers (my case), put the old key in and force it with a pair of pliers, making sure that the plier jaws are up close to the cylinder.

Again, that's a last ditch effort if the new key doesn't fix the problem.

Good luck.