This episode was listed in the TV Guide but the episode did not get shown as far as I can determine. I can only speak for part of the east coast. Unless it was picked up on the west coast perhaps.
Since it was announced in the TV Guide, it was produced, but may remain unaired to this day. If anyone DID see it, please update this with your location at the time you saw this episode.
The episode was prempted in parts of the northeast.
The episode reportedly was included in the movie compilation of several episodes described elsewhere here.
(Thanks to Raaj for the info.
This was the last episode broadcast, and ended with them still stuck in the wrong bodies so apparently they remained that way ever after.