I'm not really fully sure of the mechanics of it, but you could allow Article submissions and also allow them to be rated. This might run into the same issue that Gary mentioned above of individuals casting multiple ratings (I'm not really sure to be honest since "ratings" aren't quite the same thing as "votes"), but this might be less of a problem if you're limiting the voting/rating to only registered users.
A poll is certainly a straight-forward solution, and one nice thing about the poll is that it's concise and in one place. User usage and interaction certainly has to be a key consideration when user interaction is required/critical. If you make it too complex or involved then unless you have a dedicated community most people won't bother.