I don’t have a fix but we had the same problem on several desktops. The page remains in the cache no matter what we did. We had to go to the template settings in the backend, and change all views, iphone, handheld to use desktop view, save, delete the T3 cache, delete Joomla cache and delete the cache on each computer to get it to go back to desktop view. Even stranger is that if we loaded a different site that had iphone settings the site loaded in iphone/handheld layout as well.
You can try viewing in Private Browsing as it does not store the information as long.
Same issue whether using ie or FF5. Something is definitely not right with cache on the T3 platform and they way it is handled using newer browsers.