New IR's not appearing in Views for non-admins

Question

We are in pre-production testing for SM 2012 SP1.  We only have a few user roles beside the built in roles.  We have a 'standard' group
which has access to just about everything except for sensitive items relating to user termination, legal, etc.  We have a group which can see those sensitive items, and then we the built in administrators.  <o:p></o:p>
When non-admins create an IR or SR, it sometimes takes up to 5 minutes for the item to show up a custom “all open incidents”
view, or in a custom “my incidents” view.  In a few isolated cases, the work item did not appear for over an hour.  However, admins can see all of these work items immediately in any view that should, by criteria, be displaying it.<o:p></o:p>
What would cause a work item to display immediately in all appropriate views for admins, but not for non-admins?<o:p></o:p>

Answer 1

Sorry for the delay in updating.  Our management team got very frustrated with the performance and nearly killed the whole project.  I got them to give SM another chance with R2, hoping that some of issues would be resolved.  This issue was
not resolved.
So, I have continued testing.  I cleaned up our Queues, so we only have 4 now in the Queues list.  When I open the properties of the our custom user role, the Queue section displays our 4 queues, plus one called Work Item Group from the System
Work Item Library.  I started with selecting just 1 Incident queue, for this user role.  I created a new IR as this user, and it took nearly 15 minutes for the IR to appear in the view.  
I then modified the user role and selected the "All work items can be accessed" radio button.  I created another IR and it appeared in the view immediately.  Now, this is where it gets interesting.   I went back to the user role and set it
back to display a single queue, and the IR disappeared from the view.  It didn't appear again for another 10 minutes.
The queue that is this IR should be assigned to is quite simple.  Right now, I want it to display all incidents.  It is not looking at an advanced class, just incident.  Initially, I did not upt any criteria on it at all.  I then tried
setting it to just Active Incidents, and still the IR's takes 10-15 minutes to appear.
I still don't understand what an aggressive queue is.  Does my queue sound 'aggressive?'  The view is looking at Incident (typical), not advanced.  I don't see any obvious problems in the Workflow Status section of the Admin pane.  What
should I be looking for next?  I need to have the ability to filter queues by user roles, but it will cripple productivity if new IRs do not appear for 10-15 minutes.