In the first major bombshell of E3, Microsoft announced that the Xbox One is getting backward compatability.
Not all Xbox 360 games will be available right away, but Microsoft will update the list of compatible games as time goes on. In addition to playing your older games, you'll be able to make use of Xbox One's features, including screenshot taking, game DVR, and more.
Xbox One's backwards compatability functionality will be available to Preview Members today, with a full roll out planned for this holiday.
Microsoft also took a shot at Sony, confirming they won't charge you to play the games you already own.