I'm always impressed by how this forum looks and behaves, from a web design perspective. I've moderated forums before and I see the work that goes into that user experience, so nice work on all the little touches you have in place that make this your own.
The FAQ says this is where to go for technical suggestions. Since Inge got me to do these PEPs I've noticed that the CSS for the wiki pages differs slightly from the CSS on the forum posts. On my browser (Firefox on Ubuntu) the body text of the initial post is sliding over into the left panel, like the attached image.
I think it is from the margin-left declaration in the .rcwrapper.wikiFxclass at line 1614 of topic-show.css. I think if you overrode that with an empty declaration it might clear up what I'm seeing.
Now if no one else is seeing that and it's an isolated problem, then by all means don't worry about it. Forum still looks good, love it! :)