How long is a novel (in word count)?

I just reached 40-thousand words!

My goal is 80K words for Kings of Persia—the first draft at least. That's about 200 pages if it's a printed novel. I think the final draft might be closer to 100k, but we'll see. (Brevity is the soul of wit, after all.)

Catcher in the Rye is 73k. And if it's good enough for Holden, it's good enough for me. 

I don't think I'll ever write a book as long as Atlas Shrugged. What a horrible thing to do to your readers.

Ayn Rand	Atlas Shrugged	561,996
Charles Dickens	A Tale of Two Cities	135,420
Erich Remarque	All Quiet on the Western Front	61,922
Ernest Hemingway	The Sun Also Rises	67,707
Fyodor Dostoyevsky	Crime and Punishment	211,591
George Orwell	Nineteen Eighty-Four	88,942
Harper Lee	To Kill A Mockingbird	99,121
Harriet Beecher Stowe	Uncle Tom’s Cabin	166,622
Henry David Thoreau	Walden	114,634
J.D. Salinger	The Catcher in the Rye	73,404
James Fenimore Cooper	Last of the Mohicans	145,469
Jane Austen	Persuasion	87,978
John Knowles	A Separate Peace	56,787
John Steinback	The Grapes of Wrath	169,481
Joseph Heller	Catch-22	174,269
Kurt Vonnegut	Slaughterhouse-Five	49,459
Leo Tolstoy	War and Peace	587,287
Mark Twain	The Adventures of Huck Finn	109,571
Nathaniel Hawthorne	The Scarlet Letter	63,604
Oscar Wilde	The Picture of Dorian Gray	78,462
Ray Bradbury	Fahrenheit 451	46,118
William Faulkner	As I Lay Dying	56,695
William Golding	Lord of the Flies	59,900

I stole this from this guy: http://indefeasible.wordpress.com/2008/05/03/great-novels-and-word-count/