I tweaked the CSS for body text, because I wanted the font size just right. Now, when viewed in certain versions of IE (which ones? Older ones. I’m not sure about newer ones), old posts are GIANT while newer posts are the appropriate size. The GIANT posts are normal size when viewed on their permanent page.
So, is this just a CSS problem and something I can fix, or should we blame Internet Explorer and leave it at that?
I’m too new with CSS to address that part of your question, but in IE7 your body text looks fine to me until May 16 and then the text is quite large — this is all on your front page, I didn’t go to the permalink. All the text in your sidebar is rather large too.