NYC launches a common platform for street repairs, noise complaints, restaurant inspections, etc.

Here's the site: http://www.neighborhoods.nyc/index.html#ambiance
Choose Crown Heights and wander around. They don't seem to have NYPD events there yet, so sites like Spotcrime.com are not dead yet.

It seems like the sites will be focused on the operations of NYC government (DOB building permits, elected officials etc.) and not on conversation.

So, the Facebook groups that have cropped up for neighborhoods are not being challenged. Ditto, tiny sites like the Q at Parkside and Brooklynian.com seem as if they may lose readers who currently use them for "news", but not for conversation.

So its 311?

It includes some stuff that is not driven by 311, but -yes- it is pretty close.