http://bustle.com/ is a wonderful example of a consumer website that uses Ember. Square's payment dashboard is a great example of a web app that uses Ember. Tilde also maintains a list of users that wish to publicize their use of Ember: http://emberjs.com/ember-users/

Also there is this blog interviewing people/companies using Ember http://emberenos.com/

It's not just Ember, it's all the front end frameworks.