According to this Shacknews piece, Left 4 Dead pre-orders are now running at almost double those seen for the Orange Box last year.
"Pre-orders are now running 95% over those of The Orange Box, and we're getting set to launch the pre-release demo and television campaign to further fuel this momentum," said Valve's Doug Lombardi.
The publisher also announced yesterday that those pre-ordering the game are going to get their hands on the demo a week early, on November 6.
That's next week.
More through there.