RIA Services versus WCF Services

Question

I\'m rewriting an LOB application whose architecture is like this:

Silverlight && Windows Mobile -> WCF -> Entity Framework -> Database.

Answer 1

Regardless to the answer:

RIA Services is built on top of WCF. With the PDC release, this will be much more evident. RIA Services simplifies the client-side programming model so that it matches very closely with your server-side DomainService and entities.

For me (and I guess that for the topic author) it is not clear what RIA services provide also besides access to the DomainService (which is same thing provided by WCF)?

Thanks.