Yeah, I see them getting subscribers at a rapid pace once this launches. The launch will be crucial as they will want to make sure that initial users are spreading good word of mouth. With the large catalog Disney possesses, this service will appeal to pretty much those of all ages as yes, you have your princess fare and other WDAS/Pixar content for younger ones, but then you have Marvel and Star Wars for a more male oriented demographic that spans a wide age range for both. The Muppets are a completely separate, quirky kind of appeal. Then of course there's just things like Sister Act 3, which will give people who liked the first two films a reason to try out the service. They are even going to be reaching into some niche areas with the WDI docuseries and things like that. Not sure what stuff from Fox will be on Disney+ vs. Hulu.Speaking as someone working in the industry: the perception is Disney is the only entity with the critical mass capable of originating and sustaining compelling content worthy of an individual subscription price outside of the big 3 (Netflix, Amazon, Hulu).
We'll see if they botch this, but the industry expectation is they will become the #2 to Netflix within a year or so of launch.
I've gone over some of that before, but it really can't be overstated. The amount of content and broad appeal means that there will be something for everyone, which will be especially handy when families are thinking about getting the service.