I think it's great, but having said that I had never had the experience of the "original" DCA. From the pictures though, I can tell you that it never was overly appealing to me before. I love the theming of Buena Vista Street and keep in mind Cars Land is catering to current and future visits by todays' kids, much like Dumbo, Peter Pan and Snow White bring us back. Kids now can look back in 10/15/20 years and say "I remember seeing that in the theater!" I do the same now with Star Wars, Indy and others. Do they still need to put in some original attractions? Yes I think so, but as has been said many times before, a known quantity is always going to be the path with least resistance.
As someone from BC and having visited California several times, I look at the DCA name as referring to more of an "Adventure in California", rather than an adventure about California.