I read to my very young children at least 4 books per day, and we make regular trips to the library once a week, if not more.
My kids have good attention spans and almost never lose focus on a story, art project or even while watching a half an hour of tv (educational cartoon only). This alone makes me very glad that I chose to read to my kids starting in their infancies.
Also, they are both very advanced in their speech, which is another great benefit of reading to your children!