1. A method for estimating the performance of an information package, comprising receiving one or more values of respective attributes of an information package; obtaining, for at least one of the one or more attributes, a buzz value characterizing the level of interest in the attribute based on analysis of on-line user search activity; and providing one or more attributes and one or more buzz values as input parameters to a regression model to yield a numerical value characterizing an estimated performance of the information package, wherein the regression model is based on historical performance of a set of previous information packages relative to the one or more attributes, and provides the coefficients for the input parameters to the estimated performance of the information package.