As far as individual reviews go, 5 star or 1-10 scale.
In poll format, however, it's got to be a like/didn't like/indifferent sort of thing. Numbers are far too abstract for something like that, and what different numbers *feel* like are going to be different for each person even if they technically liked something the same amount, this creates a lack of consistency for any one number, and as a result very rarely will the most recurring number be anything other than a 1 or a 10.
Plus it's very easily misleading. For instance say 50 people voted on a poll about Ambush Bug 2 - Return of the Bug. 20 people gave the movie a 10, 9 gave it a 1. 7 gave it a 2, 8 gave it a 3, and 6 gave it a 4. Your poll would end up having a huge bar for a the 10, and fairly small bars for the smaller numbers, which would make you believe that most people liked the movie, which wouldn't be the case, the majority of people would have given it a low number, but again different numbers mean different things to different people. You can really define the difference between a 2 and a 3. So it's better to make a poll that actually tells you whether people actually liked something or not, rather than just telling you what abstract number recurred the most.