Players can start in either of two locations - I think either as "him" or as "her" - and then progress through the story making decisions and following the directions. It's a love story, so if both players choose the right paths, they end up together at the same place.
I thought this would be a great thing for a library to try - not only does it involve reading a story, but also the community. It would get people out and interacting with each other and their neighborhood, and it really sounds like fun.
I suppose any story would work, but it would be even better if it could be place-specific - perhaps following the path of a prominent local historical figure, or the growth of a local enterprise, or even highlighting local attractions or businesses. I think there are many way to make this work, but the bottom line (as I see it) is that it is a way for the library to get outside the building and doing something that people can have fun with.