Well nuts. Obviously I need to brush up my chemistry, since until I read the article, I thought you were talking about microbes that were AsHON instead of CHON, not CHONAsS instead of CHONPS. And with all the focus on DNA, there is nothing in any of the articles to indicate that the bacterium uses arsenolipids rather than phospholipids in its cell membrane, which would be a much more substantial substitution.
Whenever I hear "based on ", I immediately think the element in question forms the "backbone": all life on Earth is Carbon-based because everything else is bonded to Carbon. This isn't Arsenic-based life, it's Carbon-based life that uses (or rather, is capable of using, since it doesn't even depend on it) Arsenic in place of Phosphorous in certain critical compounds.
Whenever I hear "based on ", I immediately think the element in question forms the "backbone": all life on Earth is Carbon-based because everything else is bonded to Carbon. This isn't Arsenic-based life, it's Carbon-based life that uses (or rather, is capable of using, since it doesn't even depend on it) Arsenic in place of Phosphorous in certain critical compounds.