Reading opens your mind to new things. Just because you can't see the direct effect reading has on your thoughts doesn't mean it has no effect. It gives you better perspective so you can see things from a different point of view.
Reading has different values other than perspective as well, it gives you conversation capital so you can better relate to others.
Obviously for reading to be valuable in these ways you have to read the "right things." I tend to prefer books over blogs if I'm trying to learn something specific (but blogs are great for keeping up on current events and getting different perspectives than the mainstream media), because it gives you focus and a single thing to remember. How many blog posts can you remember from a month ago?
Reading has different values other than perspective as well, it gives you conversation capital so you can better relate to others.
Obviously for reading to be valuable in these ways you have to read the "right things." I tend to prefer books over blogs if I'm trying to learn something specific (but blogs are great for keeping up on current events and getting different perspectives than the mainstream media), because it gives you focus and a single thing to remember. How many blog posts can you remember from a month ago?