NOTE: This was an unpublished draft that for one reason or another I did not publish on the date given. In order to clear out my draft folder on 12-16-2013 I chose to publish it. However, I won't vouch for the completeness or accuracy of it, and it most likely does not reflect my opinion anymore.
I've been here in my house for a little over a decade and have friends/neighbors who have lived here way longer than 10 and some others who have live here 5 years or more who've seen and experienced enough to wear the "old timer" badge.
One big old timer complaint about our new neighbors is that you're aren't neighborly. You don't say hi, you're too busy molesting your smartphones to look up and even nod to our existence. As a woman I understand the reluctance to engage with strangers. You never know when a "good morning" is going to devolve into sexual harassment on the streets. Your best response is a simple, "morning," "afternoon," or "evening" with or without a smile and as warmly or coldly as you want as you continue to walk on about your business. If the person lives on your block, warm it up and smile, but you can keep walking. Another benefit of this practice is that it keeps you aware of your surroundings. You should be aware that someone is walking your way. You should be vaguely aware of the other people on the sidewalk. This is for your own safety.
While I'm on the topic of speaking to your neighbors and safety. Get to know your neighbors in the adjoining houses or units as best as possible, particularly if you share a party wall. This way you can gauge how you can or want to deal with them when issues come up. So you know to just call the cops if the music is too loud and you already know your neighbor is an unreasonable man with anger issues.