Definitely not milky. I did flush my system about four times, and it slowly got better (of course there is the fluid in the engine itself that doesn't drain out, so it took a number of cycles to get it even somewhat clean).

I am leaning toward rust/dirt, as it didn't look anything like a water and oil mix that I have seen, but I thought that maybe the coolant allowed the oil to mix more normally. I might just mix up some coolant and water tonight and see what it looks like to convince myself that wasn't it.

The coolant basically had the same consistency of normal coolant, but was dark brown rather than green.

Thanks,

Tom D