I actually got an advertisement in my mail for Nextdoor. I followed the instructions and plugged in my zipcode on their website. It told me that nobody had organized a group for my neighborhood, and that I could either start one myself, or sign up to be notified when someone else did.

Maybe I should have put my email address on the "waiting list", but at that point I just closed my browser and moved on.

Reminds me of a previous HN submission: http://thenextweb.com/socialmedia/2012/12/07/local-police-po...

I think the key is using this technique on already established social networks. This seems like it would only target those who have actually had crimes committed against them: I'm not going to be browsing Nextdoor if nothing has happened to me.

This has the potential to be a great example of software making a real difference. I'd never heard about nextdoor until a few days ago when my parents of all people told me how great it was and that they had heard on nextdoor of a series of break ins around our neighborhood. I've now heard greats things about nextdoor multiple times from different people since then

Nextdoor is an example of more practical/useful local social networking. Social apps/sites can serve greater needs than selling coupon deals and ads, and I hope we see more user-focused development like this (as opposed to advertiser-focussed development).

I have a feeling Nextdoor is going to be huge.

Sounds like something I'd monitor if I were going to rob a neighborhood.