We did some tuning of the kernel settings that'll fix some problems, but we're still maxing out the CPU most the time.
The new servers are due to arrive next week, sometime between the 5th and 9th. I'd like to thank once again all the people that have bought paid accounts .... you're making this too easy: when we need new servers, we just buy them now. I like that. :-)
Update: I put up a hardware page, describing all the servers.