A method and system for processing user profiles of a plurality of users in an electronic community. Noun phrases are extracted from activities of each user logged in an activity log server, each user having an existing user profile stored in a user profile and relationship database that is external to the activity log server. The existing user profiles in the user profile and relationship database are updated from the extracted noun phrases, a keyword being associated with each determined noun phrase and being within a semantic hierarchical tree, the updating based on a usage frequency of the extracted noun phrases and an importance value of the keywords.