In the Solaris online forum last week there where refereces to another scheduled Solaris 10 update, update 11 (s10u11), schedule for release the second half of 2012.
There where no other information regarding the release but it's good to see that Solaris 10 will continue to be updated a while after Solaris 11 have been released.
The scheduled also included the expected Solaris 10 8/11 release and the Solaris 11 release which probably will be available at Oracle World 2011. There was also an update scheduled for Solaris 11 the first half of 2012.
Update: You can look at the roadmap here.
Talks I have given
5 months ago