I recently commented on the more recent paper by Verlinde, so I will reference that. The recent astronomical evidence is tentative at this point. I think the issue is that emergent gravity (EG) has a different quantum vacuum structure than standard classical gravitation. The result is then similar to Schwinger's observation about the production of charged pairs of electrons and positrons. There is then I think an instanton associated with the tunneling of EG to the standard vacuum corresponding to Einstein GR. This I think should produce elementary particles or entangled elementary particles.
In reading Verlinde's paper I do think he is on to something with this. I am just not sure that it means spacetime is modified into some sort of MOND-like gravity. that in some ways we might just be stupid with this whole dichotomy between particles and EG with a different vacuum. If the mass gap between the EG vacuum and the Einstein vacuum plus DM particles is very small or zero, then in effect the two are equivalent. Seeing the world according to this modified gravity, where the EG is due to entanglement entropy physics of cosmology, and DM produced as an tunneling instanton from the EG vacuum to the Einstein spacetime may simply be entirely the same thing.
We start with the energy
$$
E~=~\frac{1}{2}NkT,
$$
for $N$ units $N~=~A/L_p^2$ of area on the holographic screen. The mass of the holographic screen is $M$ and so $E~=~Mc^2$ The temperature of a mass held above the screen with an acceleration $a$ is
$$
T~=~\frac{\hbar a}{2\pi kc}.
$$
We now compute the acceleration according to this as
$$
a~=~\frac{L_p^2 c^3}{\hbar r^2}~=~\frac{GM}{r^2},
$$
which is the acceleration of gravity.
We recognize from the energy that $E~=~TS$ that
$$
\Delta S~=~\frac{1}{T}\Delta E
$$
and from $\Delta E~=~F\Delta r$ that we recover the acceleration law. This approach alternative to considering change in entropy of the test mass,
$$
\Delta S~=~k\frac{\Delta x}{\lambda_c},
$$
for $\lambda_c~=~\hbar/mc$ the Compton wavelength of a test mass or particle of mass $m$ and $\Delta x$ a small distance between the holographic screen, or event horizon, and the test mass. We also have the Bekenstein entropy of a black hole
$$
S~=~k\frac{A}{4L_p},
$$
for $L_p~=~\sqrt{G\hbar/c^3}$. The change in entropy is similarly computed. The results are the same, but this makes more use of the idea of the holographic screen.
The objection that gravitaton does not involve entropy is a confusion with citing the Newtonian potential and force $\vec F~=~-\nabla V$ for $V~=~-GMm/r^2$ as a conservative force with the concept of evolving a holographic screen. This objection has largely been muted, and those who think clearly know this distinction.
The entropy force is in line with the idea that spacetime is built up from entanglements. Entropy $S~=~-k\sum_np_n~log~p_n$ with $p_n~=~\rho_{nn}$ and the use of relative entropy and changes of entropy is commensurate with the concept of spacetime built from entanglements.
