Definitely this. The majority of people I've worked with over the years have used a keyboard as their main interface but simply do not know how to use it. Learning the keyboard does more than just making typing faster. It enables you to banish the rat and achieve far greater overall efficiency.
It's very easy. One and only rule: Never look at your keyboard. Cover it with carboard if you cant resist looking. First week will be a pain but eventually it will just get faster.
Another good tip is to know what the "home row" is but if you've already developed a fast personal style you don't have to follow it strictly.
