There were database problems for a half of a hour, but it didn't affected all hashpower. So it's basically bad luck, but it only balances very good luck right after DDoS attacks, when we found many blocks with really tiny hashpower.

Also watching only round time isn't good enough, because hashpower (both network and pool) is climbing down, but difficulty is still high. That last 8+ hour round had "only" 7mil shares, which is not extremely bad (however it's still much worse than average).