Jag... I kid about Irvine. I did live there 1 year (almost exactly). I was up in North Woods. It is a beautifully planned out community that is very bike friendly and yes, so awesome you can live and work in the same place. To me such a plus. In fact that is the attraction of Orange County. For many years I worked in mid-Wilshire LA. You can't live near work (well you don't want too) and I had a 2 hours drive each way no matter where I lived. Never again. Now I'm Orange County based and loving it. I live in Tustin, work in Orange, have a 10 minute drive to work and an easy bike ride. Heck I can almost walk.
As for neighbors... a friend and I sat around talking about this one day. When I was a child (I grew up in LA) we knew all our neighbors. They all knew you (so if I did something wrong the neighbor, even way down the street would call mom - darn it!). We all had block parties etc.
As an adult, I hardly know my neighbors. I seldom see them. Basically everyone works and is out early and in late and doesn't like to go out and socialized. OK I'm also not the friendliest person out there saying "hi" either but I'm busy and always have things occupying my time. I guess tmes have changed and alot of us stay in our own little secure worlds. Not certain if I can say that is a good thing or not.