Rafik Robeal announced in his Just Published! Microsoft Synchronization Services for ADO.NET Beta 1.0 post of May 12, 2007 that the Beta 1 version of the Sync Services runtime for .NET 2.0+ and Visual Studio 2005 is available here. These bits are the same as those for the Sync Services runtime in Visual Studio "Orcas" Beta 1.
Updated documentation for runtime Sync Services, which also applies to the Orcas Beta 1 implementation, is available here. (It must be a cold day in hell, because the documentation preceded the binaries.)
You'll need to make a few changes to using/Imports directives and altered object and property names than have changed from the earlier versions used in Rafik's samples.
Update 5/17/2007: Rafik has updated his six sample applications for the Beta 1 runtime release.
The runtime doesn't include the graphic Sync Designer that opens when you add Orcas Beta 1's Local Database Cache template to a VB or C# project. My A Sync Services Bidirectional Test Harness blog of March 23, 2007 describes a Windows form app that synchronizes the Northwind Orders and Order_Details tables between an SQL Server 2005 Express (SSX) instance and an SQL Server 2005 Compact Edition v3.5 (SSCE) database.
Note: Converting the Test Harness from the Orcas March 2007 CTP to Orcas Beta 1 failed due to issues with the Sync Designer's generation of the Northwind.sdf database. Specifically, the Sync Designer didn't add the required LastEditDate and CreationDate fields to the SSCE Orders and Order_Details tables, which causes replication to fail with error messages about the missing fields. For more information see my Sync Designer/SSCE Version Problems with Orcas Beta 1 post in the Microsoft Synchronization Services for ADO.NET forum and Bad Error Message Connecting to SSCE v3.5 from Orcas Beta 1 in SSMSX SP2 under Vista post in the SQL Server Compact Edition forum.