Adaptation Displacement: Most people think of the 1953 film, but don't even know it was originally a musical or a book.
Harsher in Hindsight: Lorelei asking if three sleeping pills in the straight vodka is enough. Most people know how Marilyn Monroe died.
Ho Yay: "Ain't There Anyone Here For Love?" as mentioned on the main page has some pretty straightforward homosexual/bisexual undertones.
I Am Not Shazam: Several people who are familiar with this movie but have never seen it think the title is "Diamonds Are A Girl's Best Friend", after its famous musical number.
Sequelitis: But Gentlemen Marry Brunettes didn't get the two leads back, so it tried being about their daughters.
Strawman Has a Point: When confronted about her unabashed gold-digging Lorelei gives a pretty cogent speech pointing out that a man would want his daughter to marry into wealth, so why she shouldn't want that for herself?