The drummer who plays with The Who during their performance is modeled after their late drummer, Keith Moon, instead of their actual drummer at the time. This was done at the request of The Who as a tribute to Moon.
The Who's Pete Townshend did not supply his own voice. Townshend was under the assumption that his voice would be provided by another actor (similar to The Beatles' film Yellow Submarine (1968)). When he discovered he was meant to supply his own voice, he dropped out. Pete's brother, Paul Townshend (who sounds and looks very much like his brother), provided the voice instead.
On the DVD commentary, the cast and crew recall, with great amusement, that Dan Castellaneta (the voice of Homer) and The Who's Roger Daltrey were both star-struck upon meeting each other, as each was a great admirer of the other's work.
The file photo of Homer, Moe, Lenny and Carl shown during the news is a parody of the cover art of The Who's album 'Meaty Beaty Big & Bouncy'.
Springfield is split into two area codes, 636 and 939. This would put half of Springfield in Missouri (St. Louis was originally only 314, but but then it was split between 314 and 636) and the other half in Puerto Rico.