With the introduction of Role Based Access Control in Exchange 2010, it seems we have a lot of options for delegation. About 38,505 if you consider drilling down to the attribute level. If you've been tasked with creating a delegation model, it might be frustrating in the RTM version of Exchange 2010 to wrap your head around all the objects and their relationships. To facilitate this, I've put together a Pivot Table in Excel and shared it at docs.com. It shows which management roles rollup to which management role groups, which cmdlets are included in each management role, and which parameters are associated with each cmdlet (for that specific role).