For a discussion on the economic merits of prepaying a home loan mortgage, see this link (with particular attention to posts by adios, player24 and desertcat:
http://forumserver.twoplustwo.com/sh...14&fpart=1
For installment (credit card) debt, the economics are much more straightforward. You are better off paying off the debt (as opposed to the alternative of keeping the debt outstanding and maintaining an investment portfolio).
The only caveat is that you should separate some liquid assets which you can tap in case of an emergency. A few months of living expenses is ideal. Any financial assets in excess of this amount should be dedicated to repaying debt (rather than investing in financial assets).
Any opposing views will probably point out the potential benefits of having your investment portfolio generate a rate of return that is higher than your borrowing costs. For credit card debt (which is typically much costlier than mortgage debt), you are taking an unwise risk if you adopt this manner of thinkiing.