How do city wards correspond to neighborhood identity?

PoliticsPhilly makes an attempt to map Philadelphia neighborhood names onto a Ward map -- trickiest seems to be how to group closely allied neighborhoods into reasonable groups, so that you don't end up with just as many units as you started with. Some of these suggestions, like "Center City" or "North Philly" feel fairly natural; others are a bit more forced (do East Falls, Overbrook, and Westfield really mesh? how do the Northeast groupings feel?).

I'm not a native here; I'd welcome the opinions of anybody with a better feel for neighborhood identies. In many ways, the boundaries between traditional neighborhood names carry much more salience for residents than do artificial political subdivisions, and thus it's important for grassroots organizations like Neighborhood Networks to know what groupings are likely to see themselves as having common interests.