bill - 12:31 pm on Sep 3, 2012 (gmt 0)
MDSN and TechNet members got Windows 8 back on August 15. The Enterprise release was scheduled to roll out about the same time so that is probably what you're seeing now. I did not hear that Enterprise would be getting the $39.99 pricing though. Are you seeing that?
Windows 8 is scheduled for general availability on October 26, 2012. I believe this special pricing will go into effect then.