Server – CAL Licensing
The CALs for SQL will be available only for SQL Standard and BI Edition as well as Legacy Enterprise Server Licenses.

Enterprise Server Licenses will be removed from the price list on July 1, 2012*. SA only SKUs will remain and upgrade the customers to new versions of SQL.
SQL 2012 Enterprise Edition (EE) Server Licenses will have a 20 core per Server limit when upgraded to 2012. Should the hardware you want to run the SQL EE on have more than 20 Cores, you will not be able to license the Server in the Server – CAL model for SQL EE 2012. SQL CALs will need to be covered by SA and maintained in order for the customer with a SQL EE Server – CAL model to remain compliant.
*The rules differ for EA customers.
You can license each virtual machines with a server license.
Mobility rights are granted through Software Assurance.
Migration Paths for Customers with Active Software Assurance (SA)
Customers with Active SA at general availability for SQL 2012 will find DataCenter features will be moved to the SQL 2012 Enterprise Edition. DataCenter processor Licenses will be exchanged for a minimum of 8 Cores per processor or the actual number of Cores deployed, whichever is greater. Enterprise and Standard Processor Licenses will get a minimum of 4 Cores per processor license or the actual Cores deployed, whichever is greater. Those with Workgroup, Web or Small Business Edition with Software Assurance will move to SQL Server Standard including licensing rights.
Other SKU Offerings
Web licensing will be available only through
SPLA.SQL Express and Compact Edition for Mobile Embedded Database will be available as a free download. Developer Edition will be available with MSDN subscriptions or for a small fee.