IE6-7 incorrectly scrolls an applied element background for textarea field or overflows an input field in forms. Even the most common css hack suggested is to use the fixed position for background attachment, sometimes this isn’t enough.

On any default WordPress theme and on almost all commercial templates, the comments number include the trackbacks and pingbacks. This is not so good for your readers what sometimes can open an article just to see what is commented there. Surprize, almost all comments are in fact trackbacks.