Did you know the SPDisposeCheck tool?
Well on the product blog is a great post on Disposing and SP2010. named “SharePoint 2007/2010 ‘Do Not Dispose Guidance’“
And even more usefull: SPDisposeCheck using Static Analysis in TFS ( 2010 )
You can download SPDisposeCheck as FxCop Ruleset here.
Cross post of: http://stefvanhooijdonk.com/2010/02/24/spdisposecheck-and-sharepoint-2010/