Currently we have manual failover and are working on Auto failover.
We do not have support for Novell, so I would not be able to provide information on this subject.

We have MPIO for FC HBA's. Bonding for 1GB and 10GB NIC's.
iSCSI Volume Replication is synchronous and NAS Data Replication is synchronous and asynchronous. Block IO for iSCSI/NAS in latest version.

Snapshot performance can be tested with the Demo-CD for you environment to gain real world numbers, but this is usually not an issue if more then 10 are concurrently running at the same time.