Sustainability is by no means a flawless concept, or without faults, contradictions and vagueness. Sustainability is an idea and a starting point for seeking permanent solutions for a diversity of contemporary issues.
The term itself has become overused and has lacked a concrete context to maintain a level of continuity across society. That is, often times, someone saying that something is more sustainable when they really mean more energy efficient or less damaging. To be sustainable is akin to being pregnant – either you are or you are not, theres no in-between.
Many political pundits, as well as newscasters, politicians and celebrities are often found discounting sustainability and climate change because they believe that the science is "not in" or doesn't show a reason to be concerned. Also, skeptics often discuss polling data that shows that large and statistically significant portions of the United States do not believe in climate change.
However, these critics beliefs have no impact on reality. Just because many people do not believe the science, makes it no less true than if we had a consensus. In fact, scientifically speaking, we do have a worldwide consensus that climate change is happening and that we need to act now in order to prevent cataclysmic environmental, social and economic hardships from happening or being exacerbated.
The following references are critique's of sustainability in general. While there are very good critiques of sustain abilities failings, they exist more in the area of not being a rational response to the current crises, not that they are not happening or real. The video below is an example of a poignant critique against the efforts of sustainability today and the need for stronger measures to be taken.
(How Postmodern Humans Can Wake Up and Find Their Groove. with Dr. Paul Morgan, discussing the need for a sense of urgency in sustainability)