Paul, moving from an in-house to cloud deployment is pretty easy. It is a matter of copying the dbs to your hosting partner as part of your migration strategy. Any of the major Project Server hosting firms (Project Hosts and Bemo are two good ones) are great at supporting this scenario. The bigger issue is manaing the changes and capabilitites that come with Project Server 2010. I suggest consulting with a proven Project Server partner to support your successful migration. EPM Solution Partners is a network of independent consultants that specializes in providing solutions for Project Server needs. We get you the right people at the right price from a single source. You can find additional information on our web site at http://www.epmsolutionpartners.com.