As other sources also have now also found out that the next release of Solaris will be named Solaris 10 8/11 which indicates a August release. As written previously we should expect Solaris 11 around Oracle World 2011, a more precise date have been disclosed in Joerg's blog: November 2011, a year after the Solaris 11 Express release. He also speculates in a 11/11/11 release driven by marketing. I will be very interesting to se what the last year of engineering under Oracles guidance have to deliver in the final Solaris 11 release.
Last but not least the OpenIndiana project is just about to release build 151. Update: there are even beta images available here.
Solaris 10 update 10 ZFS refresh
Talks I have given
5 months ago