I welcome Tufts University's Mark Herzberg's statement that cosmological theories are heading in "rather new directions". But I am not willing to give up MOND just yet either.
Cosmological theories based on cold dark matter (CDM) might be compatible with theories based on modifed gravity (MOND) if CDM were a phase of MOND. Perhaps gravity could exist in two forms, one our normal variety and the other, essentially equivalent to CDM. Given how little we know about the structure of gravity, there are all sorts of ways gravity might have different properties (equivalent to say, reversible phases of different atomic elements, or the duality of particles and waves) in different circumstances. Once changed to the other phase, gravitons could express different interactions with other forms of matter under different circumstances, making them say, invisible to us and leaving us to call it dark matter.
Also, until we understand gravity better, we can't rule out that our observations of the universe may be disturbed by unknown particles or properties of matter and energy in ways we don't anticipate. The Baryonic Tully-Fisher observation of galaxy mass proportional to the fourth power of rotation speed vs a third power in theory does not convince me that the theories are incomplete, but rather makes me question how accurate are the observations.
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