We're currently getting scraped by a third party that's hitting the users list page on the site repeatedly, which is causing a lot of oddness and slowdowns across the site. You may see delayed notifications, double posts, or posts in the forums taking a long time to show up after you submit them. We've been seeing a lot of scraping over the past few weeks and are examining both specific solutions (banning IPs) and more general solutions to prevent the issue. Obviously that doesn't make it any easier to use the site during periods when we're getting scraped, but hopefully things will be back to normal in the next hour or so.
Sorry for the trouble.