Satisfied enough to not ask for a sequel because it had a good enough open-ended ending.
I should have treated Nana 2 as some straight-to-DVD Disney sequels and disregard its existence, because, with the overhaul of cast members (three major characters are played by new cast members... including Hachi), I figured that the cast change thing will feel more like SPEED 2 and not DARK KNIGHT. Miyazaki Aoi had made Hachi her role, infusing the characer with such (sickeningly irresistible?) cuteness that replacing Miyazaki Aoi with Yui Ichikawa is like replacing Keanu Reeves with Jason Patric, it's not going to make the fans cheer like replacing Katie Holmes with Maggie Gyllenhaal in the upcoming Batman film!
Despite knowing that the film's been both a commercial and critical disappointment, curiosity got the better of me, and I chose to watch the film.