Well it was always a park. :p Just not the type of park with slides and sandboxes. And there's already a slide (and at one time a sandbox) in the area east of Onnett.

But since it is labeled on the map, it would be nice if maybe it was made a little bigger, and given something so that players have a reason to go there (although it always has been known as a small quiet area, so I don't know).