1. A method of providing a content discovery platform for optimizing a number of social network engagements from an audience of a first user on one or more social networks, the method is implemented in one or more servers programmed to execute the method, the method comprising: retrieving social media data from users on the one or more social networks, wherein the social media data includes one or more URLs associated with one or more articles, respectively; aggregating the social media data for each URL by a number of users, actors and actions with respect to each URL; computing a social importance score for each URL of the one or more URLs as a function of the aggregated data associated with that URL so as to estimate engagement of an article associated with a URL on the one or more social networks; ranking the one or more URLs by social importance score; generating a summarization document for each URL of the one or more URLs, wherein a summarization document for each URL includes information extracted from a web page of the article that is associated with the URL and information derived from the extracted information; indexing the summarization documents relative to social importance score; selecting criteria for optimizing the number of engagements of the audience of the first user based on input data from the first user; fetching a model for optimizing the number of engagements from the audience of the first user on the one or more social networks based on the criteria selected; generating query documents with information relating to the first user; generating features as a function of data in each query document and summarization document; and applying the selected model to the features to calculate scores for each URL summarization document; and selecting one or more summarization documents to present to the first user as a function of the calculated scores for the summarization documents, wherein the presentation of summarization documents thereby enables the first user to subsequently select one or more URLs from the summarization documents for posting on the one or more social networks to receive an optimal number of social network engagements from the audience of the first user.