I choose to swaddle my little ones and see great benefits from it. Soon after they are born they are swaddled up to keep them warm and to mimic their cozy environment that they just left. I figure they were kept warm and cozy for at least 9 months, they probably would love to continue feeling that warm, cozy feeling. Once they start moving around and flailing their arms around, I find it a needed thing to swaddle. Mine have all either woken themselves up or kept themselves awake by hitting themselves in the face. :) If they are swaddled they can't do that. :)
Its also a great sleep cue for them and such an easy one! I have a routine for my infants - eat, wake time, then sleep. When its their awake time I have them unwrapped, then when its time for them to sleep, I swaddle them up. Once they learn that cue (which doesn't take long if you start doing this right away), they relax right away......generally speaking anyways. :)
Personally I love swaddling, but I know several mamas that don't do it at all. If it works, it works! Its what you think is best for your little one and how you want to train them. I didn't really swaddle my first and had a hard time teaching her to sleep. The others I've swaddled and had a much easier time.
So what's your preference?
My happy, swaddled, contended, pirate baby :)