I would vote for the old livery, but neither has ever been very becoming to me. But both are a massive improvement over the one that Northwest used in the 60's--yuck! If you say you like a plane painted white, you'll change your mind when you see one of those things for sure!
I like the red tail, that is a Northwest trademark that should remain on any new livery they create. But I honestly think they could do much better. And as silly as the 70's "squiggely" emblem was, it has a little more class than the current "N with arrow" logo.
I liked the deep blue in the 70s-80s livery much better than the gray with the red and it is on that basis only that I voted for the 70s-80s livery.
I really believe that Northwest could make a great scheme with the red tail and either deep red or deep blue stripes, and either white or bare metal. But I am not sure how it would look. Sounds like a job for "Air Orange" or one of you graphic designers out there.
By the way, why did Northwest take the "Orient" out of its name? "Northwest Orient" sounds a lot more like a worldwide airline than "Northwest Airlines", which sounds more like the name of a regional carrier.