It seems to me that "hot or not" style ratings, where the user is asked to pick a preference between two items, would be more informative and easier to interpret than star ratings or thumbs up/thumbs down ratings. I wonder why it isn't used more often.

Star ratings have problems with compression of scales at the top and bottom. You'll never know which item is someone's favorite (or least favorite) with star ratings, because typically there will be several items with the maximum or minimum number of stars.

Pair-wise comparisons are also more fun and easier for users. When I'm doing star ratings, I often find myself trying to remember what star ratings I've given to similar things that I liked a little more or a little less so that I can try to be consistent.

Pair-wise comparisons probably make more sense for items in similar categories, though. It makes a lot more sense to pick a preference between two novels than it does to pick a preference between an ice cube tray and a camp chair.