All links from your site should be checked on a regular basis to keep your external links updated. Please, no unnecessary plugins that require a download. This means no crazy comet cursors or programs that are not widely used on the net. Your pages must not have any script errors. Also try not to clutter your pages and detract the visitor from the true content you intend to display.
Load time is also an issue here.
Sites must be free of abnormally large or small font sizes. I -colored or CRaZy fonts variances will automatically disqualify your site. Chose a common font for your content such as Arial or Times New Roman. Sites that are password protected or require a membership to view the contents will not be evaluated. Keep pop-up windows to a minimum.