I have heard a lot about Spring Roo. So I really wanted to get my hands dirty in Spring Roo.
Additionally, the open source Jena technologies would be used to build the Semantics Web piece of the application. Using Protege-OWL, some OWL and RDF would be created and stored.
To make it available in the cloud, I am considering Cloud Foundry PaaS.
I'll keep you posted and let you know my progress.