Thanks so much Shawn/Oklahoma. I checked all of the things you indicated and went to the dealer armed with info. So it indeed was the vacuum hoses. Being that they were original, they were hard as a rock and pretty much dry rotted, to a point. So when they disturbed the vacuum hoses to redo the valve cover gasket and then reinstalled the OLD hoses, they had lost their seal and vacuum and thus caused the check engine light to come on.
The dealer should have seen that when it went in for the inspection or came out. I have to say that I am pretty disappointed that they mechanic didn't think twice about putting the old hoses back on.
I got them installed, and got all of the hoses changed out, the light is now off and has been off since picking up the car today. Thank goodness. :)