I can give you some advice from experience. With my first baby, we did the CIO about the same age as your baby is now and I was glad that we did. It's sooo hard to hear your baby cry and not run to him! But, you'll thank yourself in the long run because it's so nice to be able to lay your baby down, turn around, and him quietly go to sleep! (yes, it's possible!)
Establish a regular nighttime routine (it sounds like you have one). Include a nightly bath - it seems to calm them down - and follow up with some lavendar scented lotion. If you do not have one, pick up a cheap CD player so you can play lullabies (I set it so the CD will repeat itself). My kids are 2 and 5 and still need their "night-night songs" to sleep :o)
Once you've bathed baby, dressed him, fed him, read to him, lay him in his crib and rub his head, say prayers (if you do that sort of thing) and reassure him that you're nearby. Then walk away. For the 1st night, come in after 5 minutes of crying, reassure him (but don't pick him up) and then leave. Then, come in 10 minutes later, then 15 minutes, and so on. Your baby will come to realize that you are near and will know that once you lay him down, it's time for bed.
I didn't do this with my 2nd and I paid for it dearly! I would nurse him to sleep so then he got to the point where he couldn't go to sleep unless he was nursed - I became his pacifier. He didn't sleep through the night until he was 13 months!!! You can imagine how exhausted I was. I finally did the CIO method and within 3 days, he would lay quietly until he fell asleep. Whew, was I ever happy!
In conclusion, I advise you to do this early on so that you do not have to go a year without a full night's sleep like I did :o) You can do it! And your baby will not be harmed by crying it out! You are teaching him independence and the important life skill of pacifying himself to sleep. It's good for him and for your sanity :o) Good luck!