This cartoon is the first Superman story in which Clark Kent changes into his Superman costume inside a phone booth.
The design for the flying robots was later given an homage by the brilliant Hayao Miyazaki twice! One was in Farewell My Beloved Lupin (1980), where it's used (as in this short) to steal. The second is in Castle in the Sky (1986).
The front page of the Daily Planet seen around 3:33 is dated Thursday, July 19, 1945. This would be the producer, Max Fleischer's, 62nd birthday -- four years in the future when this cartoon was made.
Krypton is shown in its customary glowing green light, the same hue that illuminates Superman's worst enemy: kryptonite.
The evil genius inventor is never formally named.