Analytically, the latter is more focused and specific, while the former is more wide-ranging, but more like shooting in the dark. The latter can even be more specific. The post can be: "What makes Texas great?" and "What makes Dallas great?" instead of "What makes a place great?"
I suppose it depends on what you who are creating the post have in mind. If you are in the mood of joining some popularity contest, you pick the former approach. With a bit of luck, replies may swarmed in, covering 20 pages or more. One caveat, though. After the first 3 or 4 pages, discussion will swerve out and sidelined until everyone is talking to himself. and most of the pages are swept into the dustbin of history, and nobody would bother with the bundle any more.
I would be discrete because of my limited resources. If the title is too general, like "What is a human?", I would not view the post in the first place. "What is a woman?" Better, but still too general for me. i simply cannot afford the time and effort to think and tackle from so many diverse angles. If you are more generously-disposed, good for you. Enjoy.