It's normal from time to time, I think. My connection's really fast, but the forum does bog down at times. I've noticed this particularly when there's some troll activity going down and the mods/admin are doing deletions/edits. Other times, threads can slow down a little when someone else is posting on them at the same time.
I've noticed it bogging down from time to time. I don't know if it correlates with the number of users logged on to the forum, or if it's something else. There are an awful lot of different things that can affect your effective page rendering, some originate locally, others at the host server, others anyplace along the various paths the packets travel inbetween. the first thing to always do is delete your temporary internet files.