I am sure you already know that SP1 Beta for Visual Studio 2008 is available to download. There are plenty of enhancements that I am sure the VS folks are covering all over the net with different blogs. As a sync guy, I am on the lookout for everything new in sync and SP1 has made a lot of improvement to the Sync Designer introduced for the first time with Visual Studio 2008.
The designer was revamped quite a bit and it much more developer friendly now. The biggest improvement however is the ability to tap into SQL Server 2008 Change Tracking feature. The designer gives you the ability to use Change Tracking instead of the traditional trigger based model (a.k.a. coupled tracking as tracking columns are coupled with data columns in the base table).
Under the covers, the Sync Designer uses a newer version of the SqlAdapterBuilder to generate the adapter that works against SQL Change Tracking. The new class is part of the newer beta bits of the Sync Services for ADO.NET. Developers can dynamically generate the commands be configuring the builder to run against an instance of SQL Server 2008 with Change Tracking enabled on the target table.
Guy Burstein has written a really good post on the new changes in the sync designer with nice snapshots including the one I posted here. Make sure to check it out.