The vendor has decided that he would prefer to deliver his work via an unbundled mechanism and is no longer pursuing integration within OpenSolaris proper. As a result, this case is now withdrawn.
(I do still want to go forward with the "blkdev" and sdcard related work specified in PSARC 2009/646 and PSARC 2009/648. My own ddrdrive driver is working very well, and has proven to be a good validation of the performance characteristics of "blkdev".) - Garrett