Microsoft has just announced SQL Server 2012 Editions information on official SQL Server 2012 site.
SQL Server 2012 will be available in three main editions:
The other editions are Web, Developer and Express.
Here is the salient features of each of the edition:
There is comparison chart of various other aspect of the above editions. Please refer here.
Additionally SQL Server 2012 licensing is also explained here.
Reference: Pinal Dave (http://blog.SQLAuthority.com)