CentOS is perhaps the most popular RHEL derivative, but with CentOS/RHEL 6.0 they totally dropped the ball. There were multiple delays in getting the CentOS 6.0 release out the door and little communication to their end-users regarding its state. Over the weekend, at long last, the ISOs of CentOS 6.0 began being distributed to their external hosting mirrors.
There's this announcement on CentOS.org that the 6.0 release is now being distributed to external mirrors. The distribution process began on Friday and now on Sunday evening it seems most all mirrors have the CentOS 6.0 ISOs and packages being offered up publicly (e.g. here).
This afternoon the release announcement has finally hit the centos-announce mailing list for the i386 and x86_64 spins. This version is being released as just DVD ISOs and no longer the multiple CD installation ISO option.
More details on this release can be found via the CentOS Wiki.
In the over half-year that we've been waiting for CentOS 6.0 to arrive as the RHEL 6.0 rebuild, Red Hat Enterprise Linux 6.1 was already released. The CentOS team claims that details about CentOS 6.1 will be posted shortly and we won't be waiting an extended period of time to see the point release.
Besides the DVD installation ISO for CentOS 6.0, there are LiveCD and LiveDVD options for the two supported architectures (i386 and x86_64) along with a minimal install CD. Additionally, there's now a "Light Weight Server" CD option too. These other variants, however, have yet to be officially released but will be in the coming days.