Aye. The problem is the source of the DDoS attacks come from a rolling rotation of IP addresses. They are forever changing (sometimes changing as frequently as every 5 seconds, that is possible). Also, a lot of legitimate players (myself included) have dynamic IP addresses, meaning they change too. IP blocking will mean legit players get blocked. That and malware is constantly getting more and more sophisticated. Even legit websites get attacked and malware thrown on them so when a user visits a legit site, they get the malware, and then their PC becomes part of a botnet too. It's a very difficult problem to solve due to the ease of accessing and executing such an attack.