I picked up a book that looks very interesting:
A bit of a mouthful, but the table of contents looks very good. There are a lot of Silverlight books out there, but few that actually focus on all the other stuff you need to know outside the boundary of your client application – the hosting, services, and deployment to Windows Azure. Its got chapters focused on the hosting, working with Azure storage, RIA Services, OData services and more. I’ll write up a review here in a couple weeks after I’ve had time to make it through it.