http://www.xensource.com/PRODUCTS/Pages/myproducts.aspx
Looks like the party is just about to get started
We should have it in the portage tree in the next 7+ days.
Ouch but likely worth it for the big company's.
XenEnterprise Version 4.0 officially ships on Aug. 20 and starts at $1,599 for an annual license on a two-socket box. A perpetual license runs $2,499
Free express version:
http://www.xensource.com/products/Pages/XenExpress.aspx
