The site was down starting around 2pm Pacific time (9PM GMT) continuing until just now.
Unfortunately, it looks like those pretty, almost working, charts on the profile pages were the culprits. I've disabled them for now and will see what I can do to get them, or some other charting system, back in place ASAP.
We're switching to a new load balancer and adding an additional web server (which means disabling the archive sites for now) and we hope that this will help iron out our site performance issues.
Once that's in place, getting the Word Count Widgets and WCAPI back are the top priority, followed by the stats (both personal and regional), search, and 'posts by this user'.
--Russ Firebus