I am afraid it is but I have heard that they worked putting new stuff into it.
Would be nice to hear from someone who bought both books.
I think that book is one of the best for winter bushcraft. I have another great one called: Winter Wise Travel and Survival in Ice and Snow. I believe if you buy these two books you don't need more, they are so great and don't copy from each other. I love the Winter Wilderness companion and thought it is perfect until I found Winter Wise, there I found a lot of great info and building plans for things I missed in the wilderness companion. If I only could buy one book so I still would go for the Winter Wilderness companion. Anyhow get both books and you will have plenty to do.
cheers
Abbe