In the US, most of boys are circumcised, though the numbers are decreasing somewhat. In other parts of the world, most non-Jewish boys are not circumcised. The distinction appears to be almost entirely cultural. There is really no right or incorrect response right here, however I think one great guideline is "like papa, like kid". The papa is most likely the individual who will instruct the boy the best ways to handle his personal hygiene in this area, so taking Dad's individual circumstance into account might be a good way to make the decision. My husband is circumcised, as is our oldest son, but our more youthful son is not. He was not circumcised when we adopted him at ten months, and we selected not to add the trauma of circumcision to his life, thinking about all the other changes he had at the time. My other half needed to do some research on the subject to feel ready to instruct our kid the appropriate care of an uncircumcised penis. Our child is six, and at this point, has actually never inquired about the distinction between his penis and his older bro's and Father's.
Something to consider about circumcision-- it is a choice you have to make early. Part of the reason we picked not to have our more youthful kid circumcised was the fact that, at ten months old, it would have been far more physically unpleasant than if he had been circumcised as a newborn. I'm sure it's no walk in the park at any age, but do realize that if you do not have your son circumcised immediately, it could not be smart to change your mind a few months down the road.
A final note about circumcision- not all penises are the same. Some kids have far more foreskin than others. If your child has just a percentage of foreskin, your physician might refer to this as a "natural circumcision", and recommend that you not have a circumcision done, unless it is for religious reasons.This means that your boy's foreskin is not most likely to cause hygiene issues, nor will it be prone to infection, as are some uncircumcised penises.
It's a good idea to talk with your physician prior to you make a decision about circumcision. It's a choice that you have to feel great about, and worth the time it takes to sort out the facts.