Many sales folks have to create a month end forecast for the manager. In an ideal world ACT! would be updated as part of their day-to-day activities. In my 'real world' experience, this is not always the case. So, come close to month end there is a need to rapidly update Opportunities to get them up to date.
This situation would be made a lot easier if there was a Edit Mode for the List view in Opportunities.
Stage, Estimated Close Date and Stauts are the main ones that will need to quickly updated, but if Product (and hence Total) could be updated from the List View that would be really useful.