I've noticed it here. I've also noticed it elsewhere. My own pirate reenacting forum was experiencing huge lags about two months ago. I'm not sure how long it lasted, maybe a month. Utterly frustrated, I did some surfing on the phpbb forums, and discovered some other were having similar experiences. I wrote to my provider, they said, "yes, you site does seem slow, but it's not on our end." Not long thereafter things picked back up.
It's a mystery...