The little white dividers that separate menu items do not go all the way to the top in IE 8.
I have attached an image.
I disabled all my plugins, disabled bp daily child, put my bp daily and child in a different folder and then loaded up a fresh bp daily 3.4 into my themes, just to rule out any customisation. And I still have the problem.
I have come to totally dislike IE8 for all the problems I experience with it, but too many people are using it to ignore them.
I am using wp 3.0.1 (buddypress was disabled for this test)