NBC announced that Star Trek would be renewed for a third season during the closing credits of "The Omega Glory," broadcast on 1 March 1968. In the announcement, they also wrote "Please do not send any more letters", responding to the vast amount of mail received during the protests organized by Gene Roddenberry and Bjo Trimble.
Only episode where a victim of the Vulcan neck-pinch actually makes a sound at the time of the pinch. Normally, the neck-pinch incapacitates the victim before he/she can make a sound.
Gene Roddenberry originally wanted to produce this script early in the first season, along with Mudd's Women (1966), but NBC thought the script was weak and ordered the staff to 'shelve' it for an indefinite time to be possibly reworked and produced later on. Despite NBC still objecting against it, Roddenberry finally had his way to make "The Omega Glory" during late in the second season.
This was one of three scripts submitted to NBC (along with Where No Man Has Gone Before (1966) and Mudd's Women (1966)) when they were seeking to do a second pilot for the series. They ultimately chose to kickstart the series with "Where No Man Has Gone Before".
This is the second of three times the Enterprise encounters another Constitution-class star ship with the entire crew dead. The other two were in The Doomsday Machine (1967) and The Tholian Web (1968).