Was listening to the radio on my way home from work yesterday, and the DJ shared this interesting tidbit:

In 1993, 4 Non Blondes recorded their massive hit "What's Up". The actual lyric "what's up" is not mentoned once in the song; however the chorus is "what's going on". For fear of being sued by the Gayes Estate, the band changed the original title from "What's Going On" to "What's Up".

The result was one of the biggest hits of the 1990's, reaching #1 in over a dozen countries.