The main difference between horse slaughterhouses and cattle plants is that horses are more difficult to herd, often getting into fights en route to the holding pen. That's partly because they're raised for racing or riding, not consumption, and thus aren't accustomed to cramped quarters. (Federal transportation regulations for horses don't have a space requirement, so buyers tend to pack them in tight.) Horses also tend to be more excitable than cows—hence the blinders—and the smell of blood makes them nervous.
I kind of take issue with this part because I don't think cattle slaughter is much better than what they do for horses. Well, okay, situations might be worse for horses than cows for the various reasons outlined in the article, but I don't think that excuses the way other livestock are treated on huge factory farm conglomerations. Anytime you put profits over anything else, these animals are going to suffer.
There is a brief mention that horses in the United States are sent to Canada or Mexico for slaughter, but I think this (and its implications) should have been stressed more, because the average person reading this might think it sounds just peachy we don't really have horse slaughter in America.
Lately, I've seen the issue of horse slaughter or abuse crop up more often in non-horsey places. I recently saw this video on the Onion. At first I thought it was going to be funny but it grows more upsetting, especially when they show a few pictures. When they say they are going to roll the video, look away for a few seconds if you don't want to see the photos! I always avoid viewing this stuff because it's so upsetting. I suppose this makes me part of the masses who prefer to "just not think" about such horrible things, but just as I don't view factory farm footage because I don't feel I contribute to it (I'm vegetarian) I also don't really feel I directly contribute to horse slaughter, so I don't feel like being horrified by the footage of it. Of course, I guess this is the same type of excuse everyone comes up with to not view horrific realities.
In any case, I suppose it's good horse slaughter/abuse seems to be getting more coverage. A little awareness never hurt, right?