Is it actually easy to implement? Mebbe - the docs claim you install Solaris 10 8/7, install a patch and two packages and you're ready to rock and or roll.
So far it has been that easy to implement.
Upgraded the host yesterday, fully patched, added the two packages, flash archived the Solaris 8 host, installed the flash into the zone and ..
# zoneadm list -cv
ID NAME STATUS PATH BRAND IP
0 global running / native shared
1 solaris10_server running /opt/zones/co-web-005_noc native shared
- solaris8_server installed /opt/zones/co-ap-015_leg solaris8 shared
Presto!
Granted, I can't turn it on because the old legacy hardware is still being used and my cut-over window isn't until tomorrow but .. I'm a happy camper.