I get that too, it is usually just to one side. Every once in a while it is a very loud crack and my fingers tingle for a little while.
people always say that that crack is by far the worst to see/hear, although it feels the best and is probably my favorite.
sorry to say i don't know much, or anything, about joint cracking. if i had to guess i'd say it was all the vertibrae in your neck cracking at once, but your guess is as good as mine.