1. A system for generating an information stream summary using a display metric, comprising: a central processing unit (CPU) to execute modules, comprising: a receiver module to receive an information stream comprising a plurality of information stream items; a display metric calculation module to calculate a display metric for each of the plurality of information stream items as an indication of relevance of one such information stream item to a user by measuring social attention given to that information stream item from other users relative to at least one of the remaining information stream items, wherein the social attention is determined based on a relative degree of interest by the user in content of the information stream items by assigning a ranking to each of the information stream items based on a previous interest shown by the other users to information stream items similar to the content: a classification module to group the plurality of information stream items into one or more summary objects; a size assignment module to assign a display size to each of the one or more summary objects based on an aggregate of the calculated display metric of each of the information stream items within that summary object, wherein the display size of that summary object is relative to the aggregated calculated display metric; and a display module to display the one or more summary objects based on the assigned size in a display.