16. An affinity engine for automatically determining within an on-line community the topic/context of each on-line asset, comprising: a processor for observing usage patterns by a community associated with said asset; said processor employing automatic techniques to extract patterns from said usage; said processor identifying usefulness of an online asset by observing user implicit behaviors in connection with said usage patterns of said online asset and by extracting behavioral patterns from said observations; said processor refining said identified online asset usefulness by context, wherein the context of each online asset is automatically detected based on observed terms/topics from individual and group user behaviors when said online asset is determined to be useful based upon said individual and group user behaviors; said processor assigning to every term and phrase a term vector entry for said asset that describes a degree to which an identified asset topic has an affinity with each said term and phrase, given the observed usage patterns: said processor refining a rating of said term vector entry based on learned associations between assets derived from community navigation and usage patterns; said processor using said term vector entry ratings for any of: determining and describing a topic of said asset; determining and describing inherent relationships between topics; determining and describing inherent relationships between assets; determining and describing a current interest of a user; determining and describing similarity between a user's current interest and each asset; said observed usage patterns comprising user online search, navigation, and interaction behavior, said behavior including any of searches performed and position in user trail, assets viewed and position in user trail, dwell, range, scrolling, think time, and mouse movement on an asset, anchors and lines used in asset text, virtual bookmarks and virtual printing, and explicit downloading, emailing, printing, saving, and removing.
16. An affinity engine for automatically determining within an on-line community the topic/context of each on-line asset, comprising: a processor for observing usage patterns by a community associated with said asset; said processor employing automatic techniques to extract patterns from said usage; said processor identifying usefulness of an online asset by observing user implicit behaviors in connection with said usage patterns of said online asset and by extracting behavioral patterns from said observations; said processor refining said identified online asset usefulness by context, wherein the context of each online asset is automatically detected based on observed terms/topics from individual and group user behaviors when said online asset is determined to be useful based upon said individual and group user behaviors; said processor assigning to every term and phrase a term vector entry for said asset that describes a degree to which an identified asset topic has an affinity with each said term and phrase, given the observed usage patterns: said processor refining a rating of said term vector entry based on learned associations between assets derived from community navigation and usage patterns; said processor using said term vector entry ratings for any of: determining and describing a topic of said asset; determining and describing inherent relationships between topics; determining and describing inherent relationships between assets; determining and describing a current interest of a user; determining and describing similarity between a user's current interest and each asset; said observed usage patterns comprising user online search, navigation, and interaction behavior, said behavior including any of searches performed and position in user trail, assets viewed and position in user trail, dwell, range, scrolling, think time, and mouse movement on an asset, anchors and lines used in asset text, virtual bookmarks and virtual printing, and explicit downloading, emailing, printing, saving, and removing. 30. The apparatus of any of claim 16 , further comprising: said processor identifying communities comprising any of peer groups and expert groups based on an information context; wherein communities are nested and defined by different levels of contexts.