A method for determining active topics may include receiving topic information for a document, the information including at least one topic and a weight for each topic, where the topic relates to content of the document, and the weight represents how strongly the topic is associated with the document. User activity information for the document, including a user activity value including at least one of a number of viewers and a number of editors of the document may be received. A topic intensity for each topic may be generated and stored by multiplying the user activity value for the document by the weight of the topic in the document. The topic intensity may be monitored over time. An alert may be generated based on the topic intensity.