Gmirror/graid or hardware raid?

[Quartz]

> Being a ufs-only guy for as long as I can remember, and only used
> gmirror, I really have to dig in the ZFS terminology to better
> understand what you guys are talking about.

FWIW, there was a list of videos just posted to freebsd-fs a couple days 
ago. If you decide to jump into ZFS, after you have a handle on all the 
basics it might be worth watching these two videos:

An Introduction to the Implementation of ZFS (part 1 of 2):
http://www.youtube.com/watch?v=UP_JfUUmDZo

An Introduction to the Implementation of ZFS (part 2 of 2):
http://www.youtube.com/watch?v=l-RCLgLxuSc

... they describe how ZFS works under the hood and it might help you 
understand the why and how of ZFS' more complex parts.