Jakob Nielsen's - The Ten Most Violated Homepage Design Guidelines

Summary:

There are ten usability mistakes that about two-thirds of corporate websites make. The prevalence of these errors alone warrants attention, especially since they appear on sites with significant investment in usable design.

1. 1. Emphasize what your site offers that's of value to users and how your services differ from those of key competitors
   
2. Use a liquid layout that lets users adjust the homepage size
   
3. Use color to distinguish visited and unvisited links
   
4. Use graphics to show real content, not just to decorate your homepage
   
5. Include a tag line that explicitly summarizes what the site or company does
   
6. Make it easy to access anything recently featured on your homepage
   
7. Include a short site description in the window title
   
8. Don't use a heading to label the search area; instead use a "Search" button to the right of the box
   
9. With stock quotes, give the percentage of change, not just the points gained or lost
   
10. Don't include an active link to the homepage on the homepage

Please read the full description here - http://www.useit.com/alertbox/20031110.html