It's unclear. My dealer did say updates would be in the $300 range. If you go to Mazda's site or Denso's site, there have been zero updates as of yet for this Nav system. Pricing seems high, but I've had Acuras for years and in practice I only updated those every 2 or 3 years. Also, even the standalones need the same updates if you are interested in having the latest info each year; granted they are closer to the $100 range for each update.
I own quite a few standalone GPS units, but still get the integrated Navi in each car. While it would certainly be cheaper to use the standalone ones, in practice it's just clunky. Who wants to go to the trouble of running a cigarette wire each time. Would you want to leave the GPS up on your windshield everywhere you park your car. Would you not put it up as often because it is a pain in the neck. Compared to large, bright, touchscreen that sits right in the middle of the dash and is there 100% of the time with no extra work or clunkiness...