IMHO, there is another factor that plays into the NC/CC debate. Most NC tobacco is aged separately for several years; meaning wrapper, binder and filler are aged as individual tobaccos. Once rolled, they are sometimes aged for additional periods, but generally, the tobacco at assembly is reasonably mature. As Rob notes, this helps the NC producers to manufacture consistent smokes.
With CC's, individual aging for long periods is not the norm. Hence, the cigars are rolled with tobaccos that are young and immature. I believe this to be the single biggest influence as to why CC's age the way the do. Instead of aging separately, the tobaccos are allowed to age in harmony, marrying the flavors over a period of time to create superior cigars. Of course, there are differences in tobacco, soil, climate, etc., but the assembly and distribution of CC's is expedited since it is a major cash crop for the island.
I gotta disagree with Doc about the age thing though. Generally speaking, the older the CC the better the smoke - up to a point. Some have been known to "fall off" after a period of time. I have found that there are some excellent smokes to be had between 2 - 4 years. There is no reason to limit yourself to five years and older.