Users can start interest subgroups such as fishing, or book clubs, or public or private street groups.
The site also offers an Urgent Alerts feature which allows a resident to send an urgent text message to neighbours in an emergency.
Carterton Neighbourhood Support co-ordinator Sue Tennent said she had sent out a newsletter with details of the new website to canvass local opinions.
"I have reservations at the moment and I've just advised my people to just take care if they want to use it."
Users could choose whether to show their address on the website, or just their street, so she encouraged them to choose the option they felt comfortable with. "It's a bit like Facebook or anything else, it probably has ups and downs."
Site co-founder and managing director Casey Eden said Neighbourly was a tool for people wanting to make a difference in their community, but not sure where to start.
"We understand not everyone wants to walk the street with a clipboard or host community meetings and so Neighbourly is all about making this process simple and easy by allowing people to get the ball rolling from the comfort of their own house.
"Whilst we would love to think every suburb in NZ would embrace Neighbourly, what we suspect will happen is that there will be pockets where the tool is popular and others will catch on in time."
Mr Eden said he and co-founder Shane Bradley started the website out of concern they knew more about their overseas friends than their nextdoor neighbours.
"Most people in modern times have got very, very busy and forgotten about meeting the person next door."
The site was first rolled out in five suburbs in Auckland in late January, and went live nationally just two weeks ago. It's now accruing a thousand new members a day. While your details were only visible to verified members of your community, it paid to use common sense.
"Don't post anything you wouldn't put up on a lamp post," Mr Eden said.
"We do understand we are asking for neighbours to take a small leap of faith but we believe that what you get back in regards a supportive neighbourhood network far outweigh any negatives."APNZ