Release Date: May 4th 2012
oi_151a_prestable3 AKA oi_151a4 is a smaller bug and security fix release.
The list of changes is shown below with the notable item being the OpenSSL bump to the latest 0.9.8. The notable fixes are to the manifests that have been blocking updates so if you've been having issues pkg \[image-\]update then please try updating to this release and report any new failure modes.
As always bang on it and report issues on bugs.openindiana.org.
You can get the full repo or just pkg update from a previous version.