Microsoft have released a reference architecture guide for Windows Azure desktops.
see the following link: Click me
“Remote Desktop Services Technical Article
Summary: This document defines a set of architectural blocks for using Windows Azure Virtual Machines to create multitenant, hosted Windows desktop and application services, referred to in this document as “desktop hosting.” The primary goal is to enable hosting providers to create secure, scalable, and reliable desktop hosting solution offers for small- and medium-sized organizations with up to 1,500 users. The intended audience for this reference architecture is hosting providers who want to leverage Windows Azure infrastructure services to deliver desktop hosting services and Subscriber Access Licenses (SALs) to multiple tenants via the Microsoft Service Provider Licensing Agreement (SPLA) program. To deliver a desktop hosting solution via Microsoft’s SPLA program, hosting partners leverage Windows Server and the Windows Desktop Experience feature to deliver Windows users an application experience that is familiar to business users and consumers. Although Windows 8, Windows 7, and earlier Windows client versions are not licensed for SPLA, the Desktop Experience feature in Windows Server 2012 provides a similar user experience and application support.”
Freek Berson MVP RDS in working on a few RDS pieces in Windows Azure.
Check out his blog http://microsoftplatform.blogspot.co.uk/
Ryan Mangan's IT Blog 
Really very nice description.It’s a good news that Microsoft Publish Windows Desktop Hosting Reference.Thanks a lot for sharing.