Its a fake, the man in that video just loaded up videos of gameplay on his pre. its pretty obvious. I've seen his videos in the past for other phones, he's not very bright. HOWEVER there IS NES emulation already available on the pre, but it requires a little bit of linux and coding capabilities, Its not quite as simple as popping a cab into your phone.

To put the NES emulator on your pre would require you to root your device first.