[juiceandjuice]

A phase/state is usually tied to structure and/or energy of matter. Dark matter is the blanket term we give to particles that interact (observably) through gravitational forces.

In general, cosmology is concerned with the quantification and characteristics of dark matter through observation, so a cosmologist is likely to mean the congregation of dark matter in the universe. Particle physicists are generally concerned with direct observation and characteristics through experiment.

I don't know who messed with the wikipedia article on state of matter, but they're wrong.