I thought it only lets you save partial maps/selected areas? As in, you choose what to save. Nokia Here, saves the whole state so you can even input an address in offline mode.
edit: Yeah I just tried saving an area on Google Maps and it doesn't seem to really let me save any map larger than roughly a 30mi diameter. I started in San Jose, CA and it wouldn't really let me pan out after the map showed Palo Alto, and that's just about 30mi on direction.
Nokia Here let me navigate all the way to UCLA in offline mode.