So I don't know too much about these, but we just got a demo at work. It sounds pretty cool from what I have learned so far. It is a very light vest (not sure on the weight, but VERY light).

Here's a link for a review I found on the web. I'll update this with a little more information after we have tried it out a work a little more.

We got it at Airgas in Anchorage, but it looks like sporting goods stores are starting to carry it from what I could learn on the web. It is a new product, I think it has only been on the market for a few months.

Might be handy for hunting as it shouldn't lose any insulation value when wet and is lighweight.