MVG is an XBox fanboi. He made a number of mistakes and was intentionally misleading in this video. To cite just one example, he has a comparison chart of what you can do with each console and mentions that you can get up to 2TB in external USB storage for the Xbox. He makes no similar claim for the Wii even though many of us here hookup 2TB USB external drives to our Wii's. He's right that the Xbox plays 1990s and later arcade titles under MAME better, however. Of course I couldn't care less about that.
The Wii gives you a unique gaming experience and 100% compatibility with GameCube. The XBox isn't even close to 100% compatible with anything else. If you recognize how imperfect emulators tend to be, you'll appreciate the importance of the Wii's GC compatibility. And how with VC, VC injects, and WiiWare it is the better choice for most of us. (And I do feel sorry for anyone still using an OG Xbox as a media player. Talk about partying like it's 1999!)
You can't hook up an external USB harddrive to the Xbox.
It doesn't support it nor does the console have a stock USB port.
Granted, the controller plugs are physically modified USB 1.1 ports but even if you'd solder a normal USB port to it, you'd still be locked at the incredible slow R/W speeds of USB 1.1.
The internal drive can be upgraded to a 2TB drive tho.
With a compatible SATA-IDE bridge, you can modernise it and even place SSD's in it.