There's a guy, WestForkArmory, on The High Road who posted about hunting pigs in Texas with a suppressor. Here's the thread:
http://www.thehighroad.org/showthrea...highlight=Pigs
The gist of his comments is that although the rounds are supersonic, the suppressor makes it difficult for the pigs to determine where the shots are coming from. It also masks the muzzle flash.
After the first shot, the pigs freeze for a moment trying to figure out which way to run. This gives him an opportunity for a couple more shots before the hogs scatter.
I plan to visit Texas in a couple of weeks. I'm going to try to meet this guy and try my hand at hog hunting in the dark.