You can buy box extensions or just use longer screws to mount the receptacles or switches. It's not a problem.

Thanks for the reply. I can rest a little easier at night :)

Our electrician used adjustable boxes that can be pulled forward to accomodate the thickness of a backsplash or paneling. He showed me how to do it and it is very easy. Ask your electrician if he used such boxes.

Here they are.

Here is a link that might be useful: electrical box extenders

MY contractor (hah hah, hubby) Also didn't allow for the thicker tile (didn't listen to me!). He tiled in pretty tight to the outlet so the ones in the link won't work for us. Longer screws might do the trick, but they wont have much support.

If your tile is already covering your box you might be in the same boat as us. Maybe you solved your problem by now but...
We actually found someone in HD in the tile dept that knew where to find what we needed. The electrical dept does have the type linked above, but in the aisle NEXT to them (in our HD) they have an accordian type. They are called outlet spacer and are little strips of plastic that can fold in on themselves and basically you fold however many you need into what amount to a, well I'll call it a spacer. It slips over the screw and gives some support between the screw where it goes thru the outlet and the actual outlet box. They are like and inch wide, and as deep as you need, you only use as many "folds" as it takes. We didn't try it yet, but combined with longer screws it should work.