I was testing the theme in multiple browsers and realized there are a number of serious formatting problems when viewed in IE 8.
First, the main menu items are not picking up the color specified in the style sheet and theme options: the menu "buttons" are background color instead and the mouseover colors don't appear. (The buttons are also taking up more space than on other browsers, which is forcing the menu onto two lines.)
Second, the sidebar gets forced all the way to the bottom of the page, appearing below the content area.
Third, the border elements around each post don't appear at all when viewed in IE 8.
Fourth, when viewing a post, there's no padding between paragraph elements. I haven't changed the default padding (10px), which appears correctly in other browsers.
Fifth, and probably the least serious, the genericons don't show up; there are just empty spaces.
(This is the development site if you want to see what I mean.)
I'm guessing this is a function of the weird way IE interprets CSS, but I'm afraid I don't know how to fix that. Any ideas?
Sorry to keep bugging you!