Until now, Microsoft has not said much about the future of database mirroring post-SQL Server 2012. With the introduction of AlwaysOn availability groups, it didn’t make sense to have two very similar features over the long term. The RTM version of SQL Server 2012’s Books Online now confirms that database mirroring will be removed in a later version of SQL Server (see the section “Features Not Supported in a Future Version of SQL Server” of the topic Deprecated Database Engine Features).
Before you push the panic button, remember that it will be at least two major versions of SQL Server before this happens, so you have time to plan your exit strategy for any database participating in a DBM pair. I’ll address this topic more as time goes on, but I felt this is an important change that should be pointed out.