Oracle Enterprise Linux available [ for free! ]
Oracle Enterprise Linux is now available from the Oracle unbreakable 2 program and ISO’s can be downloaded for free – see Sergio’s blog here: http://www.orablogs.com/sergio/archives/001838.html. I heared from Dimitri Gielis on the OOW2006 that Sergio switched from the APEX team to the new linux team.
The ISO’s are based on the RedHat distributions sets but stripped from all the labels. As add-on you now can get your support from Oracle as described on linux.oracle.com and http://www.oracle.com/technologies/linux/index.html, or for starters info look here: http://technology.amis.nl/blog/?p=1386.
ISO’s are available for the 32 bit and 64 bit Linux hardware environments. Both sets are "update 4" (unsure if they were build via RedHat AS or ES versions?). RedHat EL 32 has update 8 as it’s last distro. All in all – interesting stuff.

Update:
I extracted the ISO’s and they are called R4-U4-I386-diskx (where x is 1..4), so I guess it is save to assume that they were based on RedHat 4.
They hardly bothered to change the filenames!
I hope they did a bit more on optimizing the sourcecode for Oracle and not just a find-and-replace on the Red Hat logo.