1. A method performed by a computing system for selecting a preferred machine translation of a content item, comprising: classifying the content item based on one or more categories, the categories including at least the topic of the content item; classifying a plurality of users based on one or more categories, the one or more categories including at least an interest in one or more topics; generating multiple computer-generated translations of the content item in a specified target language using configurable parameters, the multiple translations forming a set of translations; performing one or more iterations, each iteration comprising: selecting multiple groups of users based on a mapping between the one or more content item categories and the one or more user categories; submitting each translation in the set to one group of users; receiving, from each user in the group, a translation score for the reviewed translation; weighting the translation score received from each user by a user-importance factor calculated as a function of a deviation of the user's scores from average scores for previous translations; computing an aggregate score for each reviewed translation based on the weighted scores from all users in the reviewing group; determining if the iteration has produced a preferred translation, the preferred translation being a translation from the set having an aggregate score above a predetermined threshold, or a translation having an aggregate score higher than the aggregate score for all other translations in the set by a predetermined threshold; and repeating the iteration if no preferred translation has been produced; and providing the preferred machine translation in response a subsequent request for a translation of the content item.