I am currently working on Windows Mobile Application that will need to work in both online and offline modes which will be using WCF and SQL 2005 Database on the Server side.
I found the Sync Framework a few weeks ago and I have gathered some useful links to articles and downloads.
MSDN Web Cast: http://msevents.microsoft.com/CUI/WebCastEventDetails.aspx?culture=en-US&EventID=1032413045&CountryCode=US
Sync Framework Code Samples from Microsoft: http://code.msdn.microsoft.com/sync
Microsoft Synchronization Services for ADO.NET: http://www.microsoft.com/downloads/details.aspx?familyid=75FEF59F-1B5E-49BC-A21A-9EF4F34DE6FC&displaylang=en