In our team we occasionally have to discuss some applications and make approval decisions about them. We currently use ReSubj to keep track of it, but it gets really hard to keep discussion in one place, decision making conditions in another (which is our heads) and send responses through our mail client. Not talking about deadlines and replies from the applicants.
I've checked google for 'decision making software' and found some applications, none of which are fully web-based and none of which provide outside world integration (i'm talking about generating web-forms and automated actions on each decision making step - for example sending email responses constructed out of templates).
To summ it up, what we need is: tools to receive the issues, a set of tools to host the discussion (not just stupid post/comment thing, we need it more like google wave), rules and conditions that trigger automated decisions and, finally, tools that talk to the outside world when decision has been made.
So, we are now thinking about implementing our own little software. The big question is if it's worth trying to make it more than just internal tool? Do you think businesses and teams would like to buy this sort of thing?
Personally, I don't know why I would need all of the stuff you described just to make a decision. Think about it this way. If the decision was a significant one, it would be embedded in your thought process, you would not be able to forget about it. If it isn't, then there's no use spending all that time on it.
Anyway, Fogbugz comes to mind. It's not a decision maker per say, but its a tracker. I love fogbugz and actually the new version 7 allows you to easily add custom fields, so you can probably add some poll features. Fogbugz is good because the premise is simple. Track bugs so you don't forget about them, and collaborate with your team to manage the fix. Making decisions possibly has a similar worklflow. Check them out. Track bugs/Track decisions : Fogbugz!