What kind of breathability/waterproof ratings should I be looking at for a full on cold weather jacket. I'm going to be in negative degree temperatures in deep snow. I know the features I want, I just need to figure out the ratings.

My recommendation would be to go for a real solid Gore-tex or similar shell (20k-30k), maybe with some light insulation like Primaloft. I've been riding a Sessions TNT for the past season now and really like it a lot. I've ridden it everywhere from Utah mid-dump, Whistler at 75 degrees, and in everything the weather throws at Blue, and while it was a bit hot in Whistler, it is an extremely versatile piece of gear. Just layer up with some good base layers on colder days and it provides the protection you need for the deeper snow.

On the older hand, nothing beats a down coat like the puff jacket from Patagonia on a brutal cold day, but they don't offer nearly as much moisture protection in the deep stuff.

Not really a fan of down puffs. I get the layer idea, I just want a good shell, just don't know what specs I should be looking for. So 20k-30k water resistance. Should I be looking for lower or higher numbers as far as breathability? Obviously I don't want to get all swampy, but I would prefer to open the jacket when I get to warm, than be stuck with a shell that doesn't keep the wind out.

I've got a pretty nice softshell for the warmer temps. So this jacket is pretty much just for the cold and really cold days.