I'm really torn. I don't want to be disappointed if I don't get X amount of songs I haven't seen live before, so if it's going to be a disappointment I'd rather know beforehand. But, if they're going to play something like The Glass Prison or In the Name of God, I'd rather not know beforehand and let that "OMFG THEY'RE PLAYING THAT" feeling hit as they open up the song.
Though, I'm in a unique position, because I get to see them twice, two days in a row. So, I don't think I'll spoil the second one, but I'll look up the sets after that one to see if they're rotating anything.