TechWorld has an interesting article describing the storage ticking time bomb that can come into play when combining hypervisors such as VMware and Xen with SAN storage solutions.

The good news, it looks like Emulex and Q-Logic are working on a solution.  The bad news, it might cost you to upgrade the firmware on your existing adapters.

VMware will be incorporating Emulex's N-Port Virtualization capabilities very shortly.

Read the article here.