I’m currently making use of the SQL Server Change Tracking (new feature in 2008) to incrementally load our data warehouse. Per Microsoft, it's recommended to turn on Allow_Snapshot_Isolation at server level to make sure the consistency of data when using Change Tracking. I googled about this snapshot isolation stuff and ran into some very interesting discussions/blogs/articles. See below:
Hugo Kornelis, SQL Server MVP:
http://sqlblog.com/blogs/hugo_kornelis/archive/2006/07/21/Snapshot-and-integrity-part-1.aspx
http://sqlblog.com/blogs/hugo_kornelis/archive/2006/09/15/Snapshot_and_integrity_part_2.aspx
http://sqlblog.com/blogs/hugo_kornelis/archive/2006/08/25/174.aspx
http://sqlblog.com/blogs/hugo_kornelis/archive/2006/09/15/Snapshot_and_integrity_part_4.aspx
Paul Alcon:
http://www.sqlteam.com/article/transaction-isolation-and-the-new-snapshot-isolation-level
microsoft.public.sqlserver.server:
http://www.sqlnewsgroups.net/sqlserver/t11164-performance-sql2k5-with-snapshot-isolation-level-turned.aspx
Sunil Agarwal:
http://blogs.msdn.com/b/sqlserverstorageengine/archive/2008/03/30/overhead-of-row-versioning.aspx
