http://blogs.msdn.com/stevenlees/archive/2007/12/07/feedsync-design-principles.aspxThere's been a good discussion for the past couple of days on the atom-syntax list about sync, mostly focused on tombstones. It's useful to know that our primary design point for FeedSync , as Joe Cheng points out, is around "mesh sync". That is, if youen-USCommunityServer 2.1 SP1 (Build: 61025.2)http://blogs.msdn.com/stevenlees/archive/2007/12/07/feedsync-design-principles.aspx#6700424Sat, 08 Dec 2007 07:27:53 GMT91d46819-8472-40ad-a661-2c78acb4018c:6700424James Snell<P>My primary goal in this is to find a solution that scales well from the simplest use cases to the more complex in the spirit of making the simple things easy and the complex things possible. &nbsp;SSE... er, FeedSync... is a step in the right direction for the high end of that spectrum. &nbsp;For the low end, however, there are a just a few issues (like tombstones) that are rather awkward. &nbsp;Yes, as currently defined SSE could probably work, but if we can solve the problem AND avoid issues such as the possible confusion caused by representing deleted entries as entries with extensions (for instance) then we should.</P>