This is an interesting idea, bringing clothing recycling into the sale of clothes. It will apparently be available in all 48 markets worldwide. It also seems a little odd - as the article points out, H&M's business is built around disposable clothing. Nevertheless, it is a big gesture.
The business model of H&M's partner, I:CO is especially interesting. They have a pretty cool I:Counter, which is a box that enables clothes to be weighed as it is loaded, issuing vouchers for use purchasing goods in the store. When it's full, the box becomes a shipping box and is sent for recycling.
Collector I:CO: http://www.ico-spirit.com/us/Home-1.html