Simon Kuper, the co-writer of Soccernomics, has written a comprehensive piece in this weekend's Financial Times on the growth of the use of statistical analysis in football.  The article focuses on English soccer, primarily because it is the one soccer league that has demonstrated a willingness to use numbers in their match planning and player evaluation and recruitment, but it also explains how American sports and American analysts have been driving the numbers revolution in other sports.  The article is long, but it is well worth your time to read the whole thing.