Safari's Tabs on Top and Usability
Apple recently released a beta version of its Safari 4. Naturally it has some really cool new features, including a helpful and slick start screen, and cover flow for your browsing history. It's also much faster than any other browser currently out there. However there is one substantial "new feature" to the Safari 4 user interface that's been generating lots of buzz (heat might be a better word). Namely, in this new version of Safari, the tabs (which you use to browse multiple web pages simultaneously in one window) are physically located at the very top of the browser window. The address bar, and all the other web page navigation controls are now situated underneath your tabs.
Now this makes more sense, given that all of the navigation controls apply only to the active tab. In safari 3 and earlier (as well as every other Browser other than Google's Chrome as well as Opera) tabs are situated in between the navigation controls and the content, which is visually misleading when you think about it, because it confuses the hierarchy of the user interface.
But making such a dramatic change doesn't come without consequences. As mentioned earlier, bloggers have been calling Apple out on what many see as a UI gaffe (and I'm inclined to agree with them). The issues are discussed in more detail here, here and here. But in summary, the new paradigm doesn't conform to Apple's own user interface guidelines, it makes certain actions more complex and delicate, and it's frequently awkward and inconsistent with the way other application windows behave. All of this diminishes the browsing experience, despite the good intentions behind it.
The lesson here is that its not as important for a user interface to make aesthetic and logical sense as it is to be usable. What's more, logic and aesthetics can sometimes blind a UI designer into making the wrong decision. Apple's decision to position the tabs at the top of the browser window is a logical one. But by not taking into account the myriad consequences this radical move had, it's decision was the wrong. Yes, having the tabs run underneath the navigation controls makes less aesthetic and logical sense in the abstract than the new design, but unless Safari's designers and engineers can fix the issues associated with the tabs on top, that doesn't really mean all that much.