"Dark matter" refers to a fundamentally different type of matter. OK explanation here: http://en.wikipedia.org/wiki/Dark_matter
Even your reference agrees that dark matter includes planets. I stand by my assertion that the earth is "dark matter".
As I see it, cosmologists, and I have known more than a few, have no really good idea how many "dwarf stars", or "rogue planets" really exist. If all it takes to account for observed effects is postulating many more ordinary objects, which are known and fit within our current understanding of the universe, that is a more reasonable explanation than postulating enormous amounts of exotic new material which has not bene observed anywhere.