First off, you're not alone. This happens more than people think. As far as what would burn out first, I'm not gonna begin to pretend like I'd know but I know my ex did this exact thing with her 3G in the bathtub and also, if you can believe this, washed it in the wash cycle and then dried it in the dry cycle and this made it work with little error after.
First thing, DON'T TRY TO TURN IT ON (if you haven't already)
Pour a bag of white uncooked rice into a bowl.
Take the sim card out and leave the sim tray out as well (you can use your sim in another device for the time being)
Submerge the iDevice in the rice completely and let it sit for 3 or 4 days.
After this time take it out and plug it in and see if it comes on (not by pressing the power button but by restarting after leaving it plugged in).
Good luck my friend.