I really don't understand the question "is gravity a force?" It reminds me of the Feynman story:

    > "Say, Pop, I noticed something. When I pull the wagon,
    > the ball rolls to the back of the wagon. And when I'm 
    > pulling it along and I suddenly stop, the ball rolls
    > to the front of the wagon. Why is that?
    >
    > "That, nobody knows," he said. "The general principle is 
    > that things which are moving tend to keep on moving, and 
    > things which are standing still tend to stand still, unless 
    > you push them hard. This tendency is called 'inertia,' but 
    > nobody knows why it's true." Now, that's a deep 
    > understanding. He didn't just give me the name.

I don't get why this is "a deep understanding." Why should someone have to have some deep reason for believing that something at rest won't spontaneously begin moving? Should you also need a profound explanation for why things don't spontaneously change their mass or sprout kangaroo legs and start singing "La Bamba?"

And what does it mean to ask if "gravity" is not actually a "force?" The idea of a "force" is just an abstraction we use to describe our observations. How is it a deep question to ask whether we give gravity the label of "force" or not?