It must be daunting for a software vendor like Microsoft or Oracle to sort through thousands of bug reports and suggested feature requests. I do think that ISV or shareware software vendors should provide some form of system whereby users can vote for new features or bug fixes.

Regarding shareware specifically, where some users pay more than others, and a large percentage (perhaps most in some cases) don't pay at all, the votes should be weiged based on how much the user has paid into the project. For example, it could something like one dollar one vote, as opposed to one user one vote. One could think of paying users as sort of like shareholders of your sofware, even if you don't setup a legal corporate shareholder model. I think makes a lot of sense, because not only would it tend to increase revenue, but would streamline the process of how project tasks are prioritized.