There are a few things of importance :
1) As of right now, Oracle Linux 6 with the Unbreakable Kernel is certified with a number of Oracle products such as Oracle Database 11gR2 and Oracle Fusion Middleware. The certification pages in the Oracle Support portal will be updated with the latest certification status for the various products.
As always we have gone through a long period of very comprehensive testing and validation to ensure that the whole stack works really well together, with very large database workloads, middleware application workloads etc.
2) Standard certification efforts for Oracle Linux 6 with the Red Hat Compatible Kernel are in progress and we expect that to be completed in the next few months. Because of the compatibility between OL6 and RHEL6 we can then also state certification for RHEL6.
3) Oracle Linux binaries (and of course source code) have been free for download -and- use (including production, not just trial periods) since day one. You can freely redistribute the binaries, unlike many other Linux vendors where you need to pay a support subscription to even get access to the binaries. We offered both the base distribution release DVDs (OL4, OL5, OL6) and the update releases, such as 5.1, 5.2 etc. this way. Today, in this announcement, we also started to make available the bugfix and security updates released in between these update releases. So the errata streams (both binary and source code) for OL4, 5 and 6 are now free for download and use from our Oracle Linux yum server at http://yum.oracle.com. This includes uek and uek2.
The nice thing is, if you want a complete up to date system without support, use this, if you then need support, get a support subscription. Simple, convenient, effective. We have great SLA's in producing our update streams, consistency in release timing and testing of all the components.
Have at it!