Microsoft has revealed that they have successfully gotten backwards compatibility for Xbox 360 titles running on Xbox One.
Over 100 titles will be backwards compatible by the time the program launches this holiday; today’s demo featured Mass Effect. For digital games, you only have to download the game to your Xbox and start playing. For disc-based games, the download will begin as soon as you insert the disc, and you’ll have to keep the disc in the drive to play.
In addition, the games will be able to utilize Xbox One features such as game DVR, screenshots, and streaming. No additional work is required from developers to get their games backwards compatible – they just have to approve making them available on the system.
The program is available now to Xbox preview members and will officially launch this holiday.
Source: Microsoft E3 press conference