Grey matter vs White Matter?

[DeathandTaxes]

I've read some different sources some conflicting information:

White matter is myelinated, Grey Matter is not and is instead composed of mainly soma.
Another source tells me that all neurons are myelinated in the CNS, and only PNS have unmyelinated neurons. Since Grey Matter is part of CNS, I don't know what to make of this?

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[sillyjoe]

All grey matter means is a region of the brain where there is a high density of the neuronal cell bodies (as opposed to axons). White matter is composed of mostly myelinated neuronal axons.

Think of it like this.... an entire neuron, cell body, axon, and dendrite (i.e. one neuronal cell) can start in the grey matter with it's cell body and that same neuron can be found in the white matter as it's myelinated axon.

edit: It also helps to realize that this is a histological/anatomical definition, not necessarily a "functional" one. Realize that it is just a color difference due to a higher density of a certain PART of a neuron (i.e. axon vs cell body)