Today issues are summerized on the categories; overview, inbox, to be investigated, to be impemented and closed (categories translated from the Swedish version of projektplatsen).
This is very good and gives you a good overview, but spending most of my projekt time as a testproffesional I realy miss the category "to be verified". Most issuetypes progresses trough (at least) these workflow steps; inqueue (to be selected), specify (to be investigated), create (to be implemented), accept (to be verified). As I see it most issues can't be closed without some kind of verification. The missing verification step could be static testing (a review and approval), dynamic testing (live tests) or a formal acceptance done by the customer/receiver.