I dont know if this is related to the forum upgrades etc, but I have been receiving emails about replies to threads I'm watching, I click on the link in the email and when the page loads, the new reply isnt there. When looking at the the thread listing it shows the username of the last poster, yet the last post in the thread wasnt from this person. 
As an example the thread "Show off your desk", the thread listing shows the last post from timestyles (posted at 20:35 Sunday Night), yet on the last page of the thread, the last post showing is from Hollow, posted at 20:21.
I dont know if this is sitewide, but it occurs both when logged in and logged out. Ideas?