What browser do you use? FireFox? Internet Explorer? Netscape? Safari?
Are you using any of the following:
(for anyone asking why I bring this up, click on each link yourself and note that the one you regularly go to kept you logged in, while the other two logged you out. That is, of course, if you didn't log into all three or two out of the three)
There are a few serebiiforum.com variants that were used a while ago that don't work properly anymore. I believe one is http://www.serebiiforums.com/newforums along with any IPs.
Other than that, it might just mean your connection or computer is slow, and the images fail to load in time.
For me, sometimes when I load a page, it says it loaded completely, but in the place of some people's avatars, there's a link that says "____'s Avatar". This also shows when the page is not done loading, so perhaps you aren't waiting long enough.
Pokémon Tournament & League Organizer in Hawaii