The neighbourhood thing doesn't look great to be honest, but I don't think it will affect those of us outside the big cities. I doubt that anyone at Airbnb knows where Bournemouth is, never mind whether it has neighbourhoods or not. Which is actually good, because I happen to live in an area which has a totally undeserved reputation for being a bit rough!
I used to live in Brixton, London, which also had, until recently, a rather bad reputation. If I still lived there, I'd be concerned that Airbnb staff had control over how my neighbourhood was defined.
The merged guidebook thing doesn't sound like a good idea to me. I wrote my recommendations for my guests, not for the lazy host up the road who can't be bothered! Or who completely disagrees with my about what which are the good restaurants. So I am now about to delete the entries on my listing and keep a printed/emailable version for my guests alone.
The new tick boxes in the rules are OK, but they do look a bit harsh when you read them on the listing. NO this, NO that, NO the other - what I wrote in my rules previously was a bit more chatty!
On children, I think it would be easier to say "no children under the age of x" as people have different cut off points, although of course it is more complex than this. My unwritten rule is "I don't what a whole family of badly behaved children here ruining the stay of the people in the other room, but if you book both rooms, it wouldn't matter so much. I also don't want anyone who expects to bring their child for free. However if you spontaneously mention that your child is mature, quiet and well behaved, then I'll probably let you book, whatever their age"
Additional hosts - potentially useful, thank you.
