Neowin has reported that Microsoft has made a very significant change in the leaked builds of Windows Blue edition.
Internet Explorer 11 features a user agent that removes MSIE string from the user agent and adds Like Gecko.
This seems to be aimed at getting access to the same code that is served to Mozilla Firefox and webkit based browsers like Google Chrome and Apple Safari instead of code aimed at older versions of Internet Explorer.
A lot of websites currently put different code for Internet Explorer because of the lack of support for newer technologies in the earlier editions. Microsoft has improved support for web technologies in Internet Explorer 10 and the same should be applicable in Internet Explorer 11.
The company cannot rely on web publishers to update all of their web content to fix the code to support Internet Explorer 11 so this is a crude hack to get it done automatically.