Nora Ephron Dead -- Hollywood Legend Dies at 71

Nora Ephron -- the legendary Hollywood writer who penned the screenplays for "Sleepless in Seattle" and "When Harry Met Sally" -- died Tuesday after a battle with leukemia.

According to Ephron's son Jacob Bernstein, the 71-year-old had been suffering from acute myeloid leukemia ... and took a turn for the worse in recent days after coming down with pneumonia.

Ephron scored 3 Academy Award nominations in her illustrious Hollywood career ... and was widely considered one of the most powerful women in the entertainment industry.

Among her most memorable films ... "Silkwood" ... "My Blue Heaven" ... "Michael" ... "You've Got Mail" ... and "Julie and Julia."

Ephron was married to (and famously divorced) Watergate scandal reporter Carl Bernstein ... before entering her 3rd (and final) marriage to screenwriter Nicholas Pileggi.