NC30 (yellow toned), black hair and dark brown eyes here.
I bought #2, which is a beigy shade with very, very slight pink undertones that is almost imperceptible.
I took a half a lipstick off for the variety of shades (or lack thereof!). There are only two shades, and the lighter shade will be unwearable for most ladies.) This leaves a whitish cast initially but after a while it set in to match my skintone.
Effects of skin
I've been using this for a couple of months now, and I don't see that much of an effect, but it is quite moisturizing so I'll buy this again.
Very good - lasts all day. I just need minor powder touchups during the day. Only problem is that it causes powder to slide off my face (or so I think), so regular touchups are necessary for me when I use this BB cream.
Update: I bought shade #3 - much, much better. It is a beigy shade which blends very well into my skintone.