Well, the episode itself was fantastic. How the show continues to bring the funny every week even though the plots are exactly the same, I'll never know!
But as for the 3-D, having worked at a movie theater where we project digital 3D movies, (where only a combination of the glasses, shooting style, projection, and the lens gives you the "true" effect) I can give you maybe a hundred reasons why this old-school red/blue gimmick would never work for TV.
It was a weak gimmick that I hope alot of people didn't buy into. Besides, they were really bad about letting people know where they could even get the glasses.