Seems like bad gas to me, combined with your theft deterrent tripped somehow. (Thats a long shot though.) Try putting in some known "good" gas and starting with your backup key. Had a friend that his silverado would run sniffing the start fluid but not on its own. It wound up being theft deterrent tripped (so he says, but I can't prove or verify that though.)
This would be cheapest thing to try at least.
Dbn93, somewhere on here is a way to bypass the chip key portion of the antitheft, using a resistor. Maybe you could bypass it, crank the truck to get everything to "reset" with engine running. Then unbypass it to reprogram it. If this is bad advice i apologize, its just what i would do if it were mine.(Try that is) Some folks dont want to even cut a wire on their truck, but i am not one of those, lol. Good luck with your ride though!