The issues the other night were server-side. It turns out that swap space was disabled after our most recent hard drive upgrade, and over the weekend the server was freezing when it ran out of memory. I think our database pushed it over the edge, since it was running okay before this site upgrade (we're not the only site on the server). Reactivating the swap space helped, but it didn't eliminate the issue that the server is only running on 256MB of memory and half a gig of swap. On Monday night, the MySQL server was paging a lot of data out, which accounted for much of the slowdown. It turns out that I and two other heavy-hitting sites were all doing some extreme database work at the same time.

To make a long story short (too late), the server may run into the slowdown issues again from time to time. I'm looking for some memory, so if anyone has any SDRAM they are willing to part with, it would be a nice donation to the project. I don't have my old box at the moment, but maybe next month I can get it back and see what kind of memory I was using.

I haven't been able to reproduce the "doubling" issue with the private messages, but you're not the only one who reported it. You're not clicking on the submit button more than once, are you?