Bill James developed a method for predicting playoff series winners, last updated in the 1984 edition of Baseball Abstract in an essay titled "The World Series Prediction System, Revisited". At that point, it had a pretty good track record -- 73% success in predicting the winner of all the postseason series in the 20th century.
Mike Lynch over at seamheads.com used the method (without any adjustments, updates, or other tweaks) to predict the 2010 World Series -- which correctly identified the Giants.
This year, Lynch has again used the tool and tabulated the Rangers and the Cardinals according to the Bill James method.
The result: the Rangers come out as solid favorites.
(A couple of other older references to previous use of method are here and here. Other than that, I haven't found anything on the web that uses or updates the method.)