I got Hooked on Phonics for my oldest son, and he could read by the time he was in Kindergarten, but in hindsight, now that he's 20, I would not do these reading systems with my kid.
There is such a thing as pushing too much too early, which can cause stress and take some (or all) of the joy out of learning. My son was bright and by all accounts advanced, so I thought pushing him early was a good thing. Focusing on their intelligence and forcing things early often backfires, causing a perfectionist complex and a lack of effort, and there is much research to that effect. Always focus on his effort, rather than his intelligence.
If your son loves books, and is doing great as is, why change things? Just keep reading books with him and sharing that wonderful time together. What greater way of igniting a love of reading than sharing a book with mommy! Beware of inadvertently squelching his love of books and taking the joy out of learning. One of my favorite quotes about learning is: "Education is not filling a bucket, but lighting a fire." Remember that as you seek to advance your son.
I found that all 3 of my kids pretty much became the people they were meant to be, following personality types and abilities that were there since birth, and it had nothing to do with how I tried to "direct" them. The less I tried to make them BE something (and I did less with each kid), the more successful they were. My youngest was practically ignored (I was tired)and he's never gotten below an A in school.
Oh if I could just go back with my oldest son and cuddle with him on my lap giggling and reading books, instead of drilling him over stupid phonics! How much more he might have excelled in school!
Listen to Tina K., below, and Reva, above. They are right on.