To Unbreakable Linux Network subscribers, updated DTrace RPMs are now offered up for those running Oracle's spin of Red Hat Enterprise Linux. Oracle's new version of DTrace for Linux is based on their current Unbreakable Enterprise Kernel Release 2, which is derived from the Linux 2.6.39 kernel.
This second DTrace Linux beta implements the SDT (Statically Defined Tracing) provider for in-kernel static probes. There's also several bug-fixes to this latest port of DTrace from Solaris.
Oracle still considers their Linux port of DTrace to be a "work in progress" that's currently serving as a "technology preview" for Oracle Linux users. Additional details can be found in this Oracle blog post.
It was in October of last year that Oracle announced they planned to bring their DTrace technology to Linux from Solaris, following their acquisition of Sun Microsystems.