Difficult One

OK, i’m showing up on Google’s page one results which is good but I want to consolidate two domains into one. I want to move all the blogs I have on my old domain that doesn’t get any traffic and put it on my high traffic blog. Does google care about that and will it show as duplicate content? I would assume that if i moved the content from the old to the new that it would not make a difference.

Any feedback from anyone?