According to this wiki article http://en.wikipedia.org/wiki/ZFS
there are a number of zpool implementations out there. For example, OpenSolaris and derivatives are at 28. While FreeBSD 8 appears to be at version 15. Solaris 11 is at 33 etc.
The table in that article also lists some distributions are missing some features.
What is the difference between these zpool versions? is it features or are there other fundamental differences such as increased performance on newer versions?
What I'm particularly interested in are hybrid storage pools. Does FreeNAS 8 (A FreeBSD 8 based NAS? with zpool 15) support hybrid storage?
I'd love to see features matrix or something that summarizes ZFS versions. Does such a beast exist?