Paying down mortgage is usually not financially wise. It’s always been a big controversy in our household if it truly makes sense to pay off your mortgage sooner by making extra payments. I think this article very clearly reminds people if their concern is job security, holding the extra funds you have in cash makes a lot more sense than giving your money to the bank too soon. 

http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/11/23/BU0E1GFR79.DTL&tsp=1