I remember that someone did that when the video was posted last year, and it was an easter egg..

I have been searching and can't find any info about this? Got any more details/link?

The linux box was in his lab most likely in a private network, which he dialed into. He didn't dial into an isp.

Good point, but one could also take note of the number he dialed on the telephone in the video.

Indeed. It's pretty likely that voice number still has a 300 baud modem hooked up to it. Or... not.

Given that the guy's nick is phreakmonkey, I assume he took that into consideration and used a throw-away password that was gone before the video was posted.

The IP address he connects to is 10.6.105.71, I don't think he's overly concerned about other people logging into that machine over the internet (10.0.0.0/8 is a private network IP range and not routable over the public internet, just like 127.0.0.1 or 192.168.0.0/24). Also, it's pretty likely that he changed the passwords or deleted the example user accounts after he made this video, just to be sure (i.e. belt and suspenders).