Just because Gravity isn't yet fully understood does not mean it doesn't exist.
Now replace Gravity with pretty much anything.
On another note, you want to read this, this physicist thinks that gravity as we think of it is actually a pseudo-force. It is quite interesting.
http://arxiv.org/abs/1001.0785
Starting from first principles and general assumptions Newton's law of gravitation is shown to arise naturally and unavoidably in a theory in which space is emergent through a holographic scenario
Can you clarify their use of the term Holographic? I will have to read more on this
And I don't see any data supporting that gravity is a pseudo-force vs a consequence of other material physical forces. Your link doesn't substantiate anything :/ Though it does discuss some interesting points. The one I like to note is how gravity doesn't seem to play much of a role, if at all on the microscopic level, or the quantum level.. And this is to me show's that gravity may be a weak force at these levels and only becomes notable at the larger scales and higher densities vs spin.
Space is therefore literally just a storage space for information.
Now here is something that interests me. If energy is the substance of space itself, and the substance of information, what does that say in terms of their concept? We know that -1 capacity or -1 spatial space can't actually exist, and thus space isn't emergent but rather an infinite volume. Same goes for -1 energy. This is where existence itself is energy. I think the major problem is that nobody can measure zero base energy, or the zero base point of emerging properties to ever clearly understand exactly how things work. So I really don't believe in pseudo-forces. Everything must be materially and physically connected (forces and all).
However, I will take some more time reading the PDF