Windows Azure Virtual Machines (VMs) are currently in preview at www.windowsazure.com. SQL Server high availability and disaster recovery solutions are supported on Windows Azure VMs.
For AlwaysOn Availability Groups, there is currently no support for availability group listeners in Windows Azure. Also, you must work around a DHCP limitation in Windows Azure when creating Windows Server Failover Clustering (WSFC) clusters in Windows Azure. For more information, see Configuring Windows Failover Cluster in Windows Azure for AlwaysOn Availability Groups.