I saw the Auvi-Q featured in the NYT. It seems to be smaller and lighter than the epipen. It is about the size of an playing carding and about a 1/2 an inch thick. They haven't posted the weight on it, but it sure does LOOK lighter and less cumbersome.

Is it time for UL backpackers with allergies to rejoice?

http://www.auvi-q.com/epinephrine-auto-injector-size
http://www.nytimes.com/2013/02/02/business/auvi-q-challenges-epipen-with-a-new-shape-and-size.html?_r=0

Neither of the links listed a weight, so we don't know if it is lighter. The epi-pen is not all that heavy.

The form factor looks convenient, it would certainly go into a pocket better.

The current generation of epi-pens contains two doses of epi. This device doesn't say how many doses it contains. This is quite important, particularly in a wilderness setting. As a health-care provider who does not have any serious allergies I prefer to carry a vial with at least four doses of epi and a couple of syringes. I might not feel that way if I thought I would have to inject myself.