Fidor is a German online-only bank set up through a social media/community approach. Still very early days for them (the article goes on to explain that only 30% of the community members have taken up the full banking service - and in the context of the German market 45,000 is tiny) but their approach is different and interesting.
Ok, so New Zealand is probably a bit small to support an approach like this as the only way to get a new bank up and running… but it would be fascinating to try running something like this as a brand overlay over an existing bank’s services.