I just looked over the block statistics, and there seems to be quite a high % of invalid shares in the last couple of hundred blocks. Is this because of the DDOS attacks or is there some other reason for this?
We've only had 1 "real" invalid block recently. The 4 before it were all related to two problems:
1) A bad bitcoind patch that wasn't updating to the newest block and thus we were solving old blocks
2) A bad setting in the load balancer on US West which was causing the load balancer to lock up at long polls (thus stopping our blocks from getting out of the internal network).
Both of the problems have been fixed.