Well, we're running on the new host now and it looks like I was able to save all the user accounts and 9 1/2 years of posts, so I consider that a huge success.
What I couldn't save was the old forum theme, so I've had to go back to the drawing board a bit. I think a bit of change will be good anyway since the feel of the forum hasn't changed much in years. Avatars will probably need to be re-uploaded, but I'll see if I can move them over tomorrow. Attachments that were posted in the past will be moved over tomorrow. The forum statistics have been reset. I'm not sure if that can be overwritten or not, but I'm not too concerned about it.
This is actually a more-or-less clean installation of the forum software, so hopefully some of the bugs we were running into will be squashed.
Let me know if you run into any issues.
I'll continue to play around with the look and feel, and I'll eventually add the FB and news feeds back in.