It shows all of NJ when I type it in. Google Maps does show different boundaries depending on where your IP Address is from (e.g. it shows different national boundaries for IPs from Pakistan and from India), so maybe it shows something different for people in different parts of NJ.
I had it for a few months and thought it was fine. I hate the UI and UX as a whole, though. Maybe it only bothers me because that's what I'm currently studying. I'm not a fan of the lack of social features within the app (ie. Profiles, top played artists, etc). And eventually, likely within the next year or so, IIRC they're going to switch everything over to YouTube music and leave Google Play Music behind.