Test your application on SQL Server which might have millions or records. Design your own Data Virtualization algorithms and test them using the codeplex provided databases on SQL Server 2005 and 2008 available at the codeplex website
WPF also provides controls for UI Virtualization for DataSets although all the records must be stored in the memory which is an overhead.
Good data virtualization algorithms can save memory exceptions and lead to better performance. Let me know if you need my findings on the same
Θ Ω Sushant ♂