SQL Server 2005 and 2008 support 2 types of row-versioning transaction isolation levels.
- Snapshot Isolation
- Read Committed isolation with Row-Versioning
For information on the differences between the two, read this previous Q&A:
If you have used one of these types, which one did you use and why did you choose that option over the other one?
I realize this is more of a forum question (no single right answer), but I think it will be informative and is a good extension to some of the other questions asked previously. Thanks.