If you haven’t seen the latest Alertbox from Jakob Nielsen, check it out here.
This month it discusses the use of tabs on websites and it has some great points if you are doing a website design that will use them. It’s interesting to note that Jakob doesn’t differentiate between tabs that are designed to be tabs within a page and tabs that are a style applied to the navigation.
In fact, Jakob believes that tabs should be used consistently no matter where they are on the site (primary navigation or featured element). I think this would disappoint some designers who feel that tabs are a way to make primary navigation stand out when navigation is traditionally pretty simple. I agree that the most important thing though is to be conistent on your site to present a good user experience. If you are going to use tabs as navigation elements for ajax loaded sections on your site (for example) perhaps steer away from using it for primary navigation as well.