I was there! Saw the whole thing happen. We were in Frontierland and the float with a dancing chicken went by, no dancers in between, then a float with a skeleton band started coming by, and it looked at first like they were running late or something. Right after they passed us the float started speeding up, and I thought it was going faster to catch up to the rest of the parade. Not so: next DH says "holy crap that float's gonna crash into the other one." sure enough it did. It wasn't a huge deal, it didn't look like anyone got hurt but you saw the skeleton guys kind of waver or whatever when they crashed. They got off the float and headed back to where the floats come out of. At this point another float with maleficent and evil queen, etc. had come out and stopped, they just had to keep on dancing like nothing was wrong. After a couple minutes all the parade people were told to get off the floats and go back to where they came out of, and then a bunch of maintenance guys came running out. That was the end of that parade.