1000px is the new 800px

Actually it depends on your audience, as Smashing Magazine points out. However, I say 1000px is a minimum these days. My monitor is set at 1024×768 (though I could set it higher), and it’s currently on the small end. With new LCD monitors getting bigger and bigger (and it being hard to get 1024×768 LCDs) monitor widths are skyrocketing. Few people use anything lower than 1024×768 anymore, as statistics show.