Danny Sullivan wrote a famous article back about three months ago on Searching With Invisible Tabs. This article details the problem that is slowly happening to the Google search engine, where Google keeps adding tabs for users to specify if they are searching for web, images, products, news and other types of searches. Danny predicts that if Google keeps going at this rate you can expect to see dozens of tabs that turn the simple search engine query box into a complicated set of tabs.
I visited Yahoo's search homepage which I just noticed had this "Add or Remove Tabs" link on the left bottom portion of the last tab. So I clicked on it to find the ability to add a total of 9 tabs!
Yahoo! does this with class, they don't require you to have tabs but they give you the option of adding tabs if you desire. They must figure that more advanced users will opt for the tabs and there is no loss on anyones part.
Did Yahoo! miss Danny's point of "invisible tabs", the ability for a search engine to predict which tab the user wants based solely on what query is entered into the search box? Or is this just an intermediate stage until search technology can supply meaningful and accurate results based on the 'style' of how a query is entered?