ScottC, yep, there are meta tags for that. I'll look into how much it may affect our servers's performance... thanks for the tip.

monahos, you mention "the non-updated page problem goes away if I open a thread using the 'open in new window' function, which gives the full URL in the address bar"

That seems to indicate to me that some type of caching is going on at your end, although we can't seem to narrow it down. Also, you mentioned that you're experiencing this type of problem on other sites now.

I'm stumped But at least you can get a refreshed page by opening a new window...