In the 1st season, in a couple episodes, Ethel was a really good piano player, in this episode, she barely knows how to play.
The same issue of the New York Gazette, with the same "Bond Issue Defeated" headline has been seen previously in several different episodes.
The magazines on sale at the newsstand include the November 2, 1953 issue of "Life", the December 1953 issue of "Art Photography", the January 12, February 26 and March 12, 1954 issues of "TV Guide" and the February 1954 issue of "Auto Age".
Right before the (all male) all "girl" orchestra begins playing at the club dance, you can hear Lucille Ball laughing loudly. Her laugh is the very last one that you hear.