1.) Inappropriate use of flash on the home page.
2.) High bandwidth/slow download. It is particularly important that the home page download quickly.
3.) Poor navigation and search technology. If consumers are using Google to search your website rather than your search engine, you need to redesign your site.
4.) Font that is too small and poor print/contrast ratio. White space is your friend, so are large fonts. Sans serif seems to work better on the web.
5.) Use of PDF for your press releases. Why make an extra step to read your news? Press releases should be in HTML with the contact information at the top. If you are announcing a partnership, you might want to hyperlink to your partner’s site.
John Horton has a terrific paper on how to use AJAX technology to create a more dynamic and informative website.
You might also ask your web team if they are familiar with Section 508 requirements. Only federal sites are mandated to meet Section 508 requirements, but it is very good PR to make your site accessible.
More information on common problems with web design.
Best Practices in Online Media Relations: Utilizing Internet Newsrooms and RSS to deliver on Strategic Communications Objectives