Me: one brother & his wife, my parents, 3 of 4 grand-parents (all in their 80s and living like they're in their 50s!), 3 paternal aunts/uncles still alive, one with spouse and 3 kids. 3 maternal aunts/uncles and their spouses, 1, 2, and 3 kids respectively. a couple of my cousins have kids. The extended maternal clan is probably about 50+ with great aunts, 2nd cousins, and other types of folks I only see at the family reunion. Dad's extended fam is about the same, though we don't visit them as often. My bro and i haven't had kids, I probably won't for reasons both health-and personality-related, Brother probably will once SIL finishes up grad school.
DH: Only child; His mom; one of 2 maternal uncles, wife, and 6(!)kids; both paternal uncles, their wives/SOs and kids, 2 of 4 grandparents (maternal), miscellaneous cousins, great-aunts, etc that he only sees at reunions and such.
All told, not quite 30 on my side, about 20 on DH's. the families are definitely shrinking with each generation, but we're both from the south and that seems to be the trend around here.