The 2006 edition of the Research-Based Web Design & Usability Guidelines is now available. Compiled by the United States Department of Health and Human Services, the guide is typically used for government websites but has also become a resource for all web designers wanting to build usable websites.

The guide is free for download, but at a hefty 157MB, your best option might be to pay $25 for a hard copy at the US Government Bookstore.

Twenty-two new guidelines have been added, including the following hot topics:

• Involving users in establishing user requirements
• Using personas to design more effective web sites
• Formatting information for reading or printing
• Distinguishing between frequency and severity of usability issues

There are also some new guidelines that are sure to be more controversial, including the following:

• Using fluid layouts
• Placing primary navigation menus in the left panel
• Using static menus

Web site notusable has also published an “ultimate webdesign usability checklist” that might be of interest to usability gurus.