After Paypal.com and EBay, finally Microsoft starts using EV certificates on one of their websites and it is the most important one. The Windows Live ID (passport) verification site login.live.com.
When you sign in now you will see the address bar turn green in IE7.
More info: EV certificates
Microsoft, Windows Live, login.live.com, Security, SSL, Extended Velidation Certificate, Live ID, Web Security