Of course, it can't be part of the main Toobworld, and I'm not sure it belongs anywhere in the TV Universe. Too many factors had to be changed in the characters' lives just to get to the point where this leads off and that would ruin the dynamic for both series.
Now, if they had only kept it simple and had Hiro appear at the "Casino Night" held by the Dunder-Mifflin staff in Scranton, using the 'Heroes' footage of Hiro at the casino in Las Vegas, then that might have been more acceptable.
Still, there is one thing I'm thankful for, having seen this video. I'm now a fan of the music of Mike Doughty. I LOVE "I Hear The Bells", and I've gone on to watch several other videos based on his songs.