We've been under attack since yesterday afternoon PDT. We are finding and fixing holes as fast as possible. As long as you can connect to the pool mining, it is still good to go. Our main goal is to provide the miners with the best service and profitability possible. Keeping a failover server will keep losses to a minimum while we get through these growing pains.
If any of the other crypto currency services want to team up to share techniques and ideas to prevent attacks on the community we would love to hear from you.