Still unconfirmed rumors, but my sources inside Microsoft has told me that the RTM version is delayed to November 2007.
The official RTM date is still Q3 2007.

When I have more documented information I'll update this post.

Update #1 (17-08-2007):
SCCM will be released Nov 1th. and the World Wilde launch will be announced at IT Forum in Barcelona Nov 11th.
But the RTM version might be avalible for TAP, Early Adapters and on MSDN earlier.

Update #2 (19-08-2007)
There's no such delay for "RTM" -- Release To Manufacturing.  But "General Availability" will be later than RTM, and that may be the cause of the confusion and the November date.

Michael Kelley
Lead Program Manager
Configuration Manager 2007