One of the coolest technologies Microsoft released with SQL Server 2005 was Database Mirroring, which provided the ability to have a failover copy of a database on another SQL Server instance, and have the ability to automatically failover to that copy should a problem occur with the primary database. What was even cooler was that this new technology was available on Standard Edition! Mom and Pop shops could afford to implement a high availability solution without paying an extra tens of thousands of dollars in license fees, and still have a service they could rely upon. This new technology was continued with SQL Server 2008 and SQL Server 2008 R2, with the same edition rules, and now lots of companies embrace it fully.
When we first started discussing Availability Groups, the new "Always On" technology that was introduced with SQL Server 2012 with Microsoft, the development team told us that it would "leverage" the clustering services technology built into the Windows Operating System. I was extremely upset with this decision because at that time, clustering services was only supported in the Enterprise Edition of Windows Server. (I was vocal enough about it that Michael Coles (blog) started calling me "Mr. Standard Edition".)
The good news about Windows Clustering Services is that it's now supported in Standard Edition on Windows Server 2012.
The bad news about Availability Groups is that it's only supported in Enterprise Edition of SQL Server 2012. Oh, and by the way, Database Mirroring is now deprecated.
Now, deprecated doesn't mean it's gone, just that it's scheduled to be removed from the product in a future release. (Isn't that comforting?)
Personally, I think that in the interest in competing with Oracle and DB2, Microsoft is abandoning the client base that got them to the point where they CAN compete with Oracle and DB2, and that isn't good, for the client base or for Microsoft. Customers have come to rely on Microsoft to put out a great product at a reasonable price. This focus on Enterprise Only for all mission-critical features puts SQL Server out of reach for startup businesses. (Yes, I know there's now Windows Azure SQL Database, but if you're in a place where your internet connectivity isn't always reliable you have no reasonably priced solution.)
My request to Microsoft is to please continue to support Database Mirroring, and remove the "deprecated" label from that technology. It works, it's reasonably easy to implement, and it provides some level of comfort that ensures that businesses can continue to operate if a server fails for any reason.