Pros: fresh eggs are better, and homegrown hens aren't full of hormones and antibiotics. Good project for the kids too, and hens can be entertaining.
Cons: could be smelly if your neighbour doesn't clean the coop, and some people believe that chickens will attract bears and other varmints. Noise shouldn't be an issue since home coops are limited to hens, not roosters.
* a jingle from my childhood in Calgary