It should be pointed out that String theory and Quantum gravity are big topics in modern physics, but that does not mean that the physics of newton does not work. If I take my pencil and drop it, it will still hit the floor (or maybe my foot), and the path it takes will follow the laws set down by Newton 300+ years ago.
What is going on here is trying to understand gravity at a very deep level and understand what it will do on very large scales or in very extreme cases such as near a black hole, in these cases we are not sure on exactly how the laws of physics work. The basics and the common cases we understand quite well, its the strange and the extreme that is still being worked on.
–Zach (Who once considered doing physics for a living)