Some of you kernel hackers may be interested to know about my case (PSARC 2009/380) that eliminates one of the ancient limitations of Solaris -- having STREAMS and non-STREAMS entry points in the same device driver. I've also implemented it and am waiting for the case to time out before I submit the RTI.
As part of this, I also implemented a set of changes to the audio stack -- the austr(7D) "speecial" node and driver goes away, and the Sun audio personality sheds about 1,000 lines of complexity. I'll be pushing those changes later, once I've gotten code review feedback. (If you review the changes, please let me know!)