Either IE's not accepting the text-indent property that makes the text overflow out of the avatar box, or it's not properly handling white-space:nowrap that prevents that text from wrapping down to a new line (looks like the latter because it appears there's an empty line before the actual text). Line 186 of the CSS:
Code:
.avatar .img {
background-position:2px 2px;
background-repeat:no-repeat;
display:block;
overflow:hidden;
text-indent:1000px;
white-space:nowrap;
}