Cameron Neylon talks about how misusing the journal impact factor can damage your science:
... Even a cursory look at the basic statistics should tell any half-competent scientist with an ounce of quantitative analysis in their bones that the Impact Factor of journals in which a given researcher publishes tells you nothing whatsoever about the quality of their work.
... if as professional researchers we don't have the integrity to challenge the fundamental methodological flaws in using JIFs to judge people and the appalling distortion of scientific communication that this creates then I question whether our own research methodology can be trusted either.
My personal belief is that we should be focussing on developing effective and diverse measures of the re-use of research outputs. By measuring use rather than merely prestige we can go much of the way of delivering on the so-called impact agenda, optimising our use of public funds to generate outcomes but while retaining some say over the types of outcomes that are important and what timeframes they are measured over...