As unfortunate as it may be, it's never a Valve release without delays. While already available on Xbox 360, the PC version of the Left 4 Dead 2 demo has been re-scheduled to hit Steam tomorrow, a day later than originally planned.
"The Left 4 Dead 2 Xbox 360 Demo is now available for those who pre-ordered and obtained early access to the demo. The PC Demo is currently targeted for release on Wednesday, October 28," noted the company in a statement.
While no reason for the abrupt delay was given, we'd assume that some unforeseen last-minute issues prompted the setback. For what its worth, the dedicated server files are now available, which gives us a little assurance that things are on the move.