Stole coins from everyone on his pool. We had anywhere between 1/4 to 1/10th of the network hashing and his site constantly reported that we would find only 2 out of the last 100 blocks for hours on 5/4. He claimed it was due to a DDOS, but then later stated that the pool had been miscounting blocks and he had over 5000 coins that he'd credit. This is a pplns pool and I received credit for 6 blocks after complaining. 5000 coins is more like 56 blocks the pool should've seen. After everyone complained he shut the pool down.
Original thread here https://bitcointalk.org/index.php?topic=193481.220