Reggie870 said:
We had to have ours replaced for the exact same thing. One day the wife calls me and says the key won't go into the ignition. Dealership tried blaming us for it saying it was damaged and it would not be covered under warranty. We told them our views on it and it was replaced.
I also had the "Key won't go into the Ignition Switch" issue, twice in early '06.
There is a white piece of plastic in the entrance way of the switch, which is spring loaded. If it gets cocked out of place, you are locked out.
I had a discussion with said plastic using a BELL "C" flat head screwdriver (actually two conversations with that little bugger), and no problems since then.