Looks welded.
1) Fix it right - cut off the part of the hanger that sticks up, and weld a new one on the other side. [like Joebot said] I wouldn't try to "unweld" the old hanger for fear the pipe would get ruined.
2) Quick fix (I probably would have done already
) - buy a bolt on clamp from an auto parts store, bolt it on in the right position (or close enough) and leave the old hanger as is. I doesn't look like it would hit / rub on anything if the new hanger was in the right position.
Or do #2 above while waiting for #1
Keep in mind my most common exhaust repairs include baling wire (albeit on beater cars), so you might not want to listen to me.