Mac OS X Server Software Support now includes Xsan Support
Those of you with large installations have probably considered Apple's Select, Preferred, or Alliance Support plans.
As of today, these plans include support for Xsan. This means a separate agreement for Xsan is no longer necessary.
It isn't too common to witness Apple forgoing a revenue opportunity. Optimistically, this is a sign of Xsan's maturity and ubiquity.



that gives you direct access—24 hours a day, 7 days a week— to Apple’s
dedicated Xsan Support team.
http://store.apple.com/us/product/M9754ZM/B