Solution - 1

Specify height and width would be useful for floating content on IE7, since IE up to 7 will use its content to determine width on floating element (box model bug), not to mention you use header tag for a description not div or p.

Solution - 2

replace

.gform_wrapper .top_label .gfield_label {
    clear: both;
    display: inline-block;
    font-weight: bold;
    line-height: 1.3em;
    margin: 10px 0 4px;
}

.gform_wrapper .top_label .gfield_label {
    clear: both;
    display: block;
    font-weight: bold;
    line-height: 1.3em;
    margin: 10px 0 4px;
}

Solution - 3

I can only see the background image. No content at all.

Solution - 4

Hi Teggen, It seems you must be running IE8 in compatibility mode, because the page displays ok in my IE8, but goes haywire when I send the browser into compatibility mode. Anyway, your problem seems to be the

float:right;