SQL Azure Upgrade Advisor? Here you go...
Get your SQL Server database ready for SQL Azure! - SQL Server Team Blog - Site Home - TechNet Blogs: "One of our lab project teams was pretty busy while the rest of us were taking a break between Christmas and New Year’s here in Redmond. On January 3rd, their new lab went live: Microsoft Codename "SQL Azure Compatibility Assessment". This lab is an experimental cloud service targeted at database developers and admins who are considering migrating existing SQL Server databases into SQL Azure databases and want to know how easy or hard this process is going to be. SQL Azure, as you may already know, is a highly available and scalable cloud database service delivered from Microsoft’s datacenters. This lab helps in getting your SQL Server database cloud-ready by pointing out schema objects which are not supported in SQL Azure and need to be changed prior to the migration process. So if you are thinking about the cloud again coming out of a strong holiday season where some of your on-premises databases were getting tough to manage due to increased load, this lab may be worth checking out."
'via Blog this'
Based on the recent training course I took using SQL Azure, the backend is a SQL 2005 "Express" style instance. Lack of some key "newer" features that use the CLR (datatypes like spatial and xml) may quickly exclude some of your more complex databases from being migrated to the cloud.