Also in the past few hours bouncing around the site..

I have seen JavaScript warnings due to the script being non-ECMA compliant, and a load of CSS warnings.

Example:

font-style:bold;

instead of font-weight: bold;

Also several references to MS filter style rules, and even some pages reporting they are being rendered in Quirks mode.

Your pages could render faster with less repainting with proper markup, CSS, and JavaScript coding practices.