Going Green the Vegan Way - is it sustainable?

I have been a vegetarian for 20 years. About a year and a half ago I changed my eating habits to include more organic foods and removed all dairy products from my diet, making that subtle change to a vegan. Quite a bit of discussion has been given to this topic and I wanted to share a nuance that some may see as not sustainable! *Taken from the Good Human

Sustainability and waste of resources. More than 70 percent of the grains and cereals we grow go to feed animals. If that food were to go to humans instead, it would be enough to feed everyone in the world. Another fact: half the water used in the United States and nearly 80 percent of the land are used to raise animals.
Eating animals causes global warming. A major report by the University of Chicago in 2006 found that adopting a vegan diet has a greater impact in the fight against global warming than switching to a hybrid car does.
Worker rights. The fast line speeds, dirty killing floors, and lack of training make animal-processing plants some of the most dangerous places to work in America today. Nearly one in three slaughterhouse workers suffers from illness or injury every year, compared to one in 10 workers in other manufacturing jobs. The rate of repetitive stress injury for slaughterhouse employees is 35 times higher than it is for those with other manufacturing jobs.
World hunger. Land, water and other resources that could be used to feed humans are being used to grow crops for farmed animals instead. Crops that could be used to feed the hungry are instead being used to fatten farm animals raised for food. Eating meat is inherently inefficient, as it takes 16 pounds of grain to produce 1 pound of flesh. And because the industrial world is exporting grain to developing countries and importing the meat that is produced with it, farmers who are trying to feed themselves are being driven off their land.

So, what do you think? I think it makes a great case for why sustainable practice should include diet!?!?