The difference is that we have found (indirectly) many organic molecules, even in deep space: http://en.wikipedia.org/wiki/List_of_interstellar_and_circum... (most of the molecules with more than 4 atoms are organic)

So, finding some organic molecules in Mars is totally expected. On the other hand, finding a any proof of life in Mars would be amazing, but as far as I understand this "report" is only an uniformed speculation.