Microsoft says ‘Internet Explorer 11 is the first browser to make Internet connections more secure and reliable by reducing the use of vulnerable cipher suites, such as RC4 and by using the latest security standards, TLS 1.2, by default.’
Read more about how IE11 reduces the use of vulnerable RC4 Cipher Suite, and turning on TLS 1.2 by Default – http://blogs.msdn.com/b/ie/archive/2013/11/12/ie11-automatically-makes-over-40-of-the-web-more-secure-while-making-sure-sites-continue-to-work.aspx