Yep!! It sure is Kate! Personally, I haven't tried carrying two, as I only have one carry-ee. So I can't speak from experience, yet.

Get your friend to go and check out thebabywearer. Or google baby carriers downunder and join the google group - there are a few members who either carry twins, or a toddler and newborn and I'm sure they would love to help her find the babywearing love.

I've seen on ebay some very scary, and uncomfortable looking carriers that are designed for twins. As far as I'm aware, there are no good carriers recommended by any babywearing groups that are specifically designed for twins. But, there are ways to use two carriers (eg: two rings slings - one on each shoulder, or two wraps or one longer wrap, or a mei-tai front and back) that will give the most flexibility and comfort.