In this MSDN article there is information about what I understand is an "native" way of doing change tracking in relation to building applications for Sync Framework in SQL Server 2008, it that the CHECKSUM(), BINARY_CHECKSUM(), and CHECKSUM_AGG() functions mentioned in the article or is it a third way?

How to: Use SQL Server Change Tracking http://msdn.microsoft.com/en-us/library/cc305322.aspx%5B/url%5D