It would also be nice to be able to assign an "expiration date" to tasks, so that the ones you never complete (presumably because they don't really matter) could either be deleted or archived to a "someday" folder.
That is a very interesting idea. I like it! But, I also might worry (fail to trust the system) if I didn't have a handle on things and this happened automatically. It may be better to have that "failure" continue to glare at me in my list for awhile before I sent it off to slumber in a someday folder.
I really like the sounds of automatic prioritization through ranking. I think I'd kill for it, to be frank. I'd be more than happy to give up any manual prioritization system for an automatic prioritization by dragging in a list.