Oh I dunno, I think that pretty much covers it for must reads for anyone. If you're thinking of epic things that advanced the art or were just extraordinarily popular. eh.. maybe add:
Margaret Weis and Tracy Hickman for "The Dragonlance Chronicles",
George R.R. Martin for "Song of Ice and Fire",
David Eddings for "The Belgariad"
Raymond Feist for "The Riftwar Saga"
Tad Williams for "Memory, Sorrow and Thorn"
Lots of great fantasy in
this thread.