The latest Solaris release does seem to contain the changes described in PSARC 2008/769, however it still creates zpools on a WD20EARS drive (with 4K physical sectors) with an ashift value of 9.
I am not sure what the reason for this is. Most likely the WD drives do not tell the truth even about their physical sector size. What a pity. So, my workaround (the modified zpool program) is still necessary.
There is one more issue with these disks. Allegedly they unload their heads after an idle period of only 8 seconds. Many users have reported very high head load/unload counts as reported in S.M.A.R.T. data. As a precaution, I have put
set zfs:zfs_txg_timeout = 5
into /etc/system. The default in s10u9 is still 30 seconds, although the latest opensolaris code (as of mid-August, when Oracle stopped their putbacks) also sets it to 5 seconds. This should keep the disk busy in case of sporadic updates