Hoping you can address this in your next fix...
Using Windows XP SP3 and Google Chrome 8.0.552.224, threads often scroll off the right side of the browser window at 1024x600 resolution. This is the most common netbook resolution. Posts display within the viewport as long as there's an ad beside them. however, the first post after the ads extends well off the edge of the viewport. This issue is fine in IE6.0. Didn't test in Firefox.
See the following screenshot. The topmost post is fine (the top of the post is aligned with an ad box), but the next post scrolls off the right side of the screen.