SQL Server 2012, Network for: AlwaysOn Availability Group with AlwaysOn AlwaysOn Failover Cluster Instances

Question

Setup: I have two data centers. In site1, my primary site, I'd like to deploy an AlwaysOn Failover Cluster Instance (FCI). In site2, my data recovery site, I'd like to deploy a single-node instance of SQL. I'd then like to use AlwaysOn Availability Groups (AG) to replicate data between site1 and site2.

I've read a lot of blog posts and TechNet articles. It's clear to me that automatic fail over is not supported for AGs with FCI members [1]. It's also clear that FCIs support nodes on multiple subnets [2]. Apparently this is achieved by updating the Virtual Network Name (VNN) in DNS.

Question: Do AGs support multiple subnets, or do I need a spanned subnet between site1 and site2? I haven't been able to find any sources that explicitly make that clear.

References:

[1] Failover Clustering and AlwaysOn Availability Groups (SQL Server) http://msdn.microsoft.com/en-us/library/ff929171.aspx

[2] AlwaysOn Failover Cluster Instances (SQL Server) http://msdn.microsoft.com/en-us/library/ms189134.aspx