Ted, I think Apple and most other big brands would answer your last question by saying, yes, they take responsibility for the actions in their supply chain.
I don't want to excuse of minimize the problems at Foxconn--in fact, I intend to write about them very soon--but two points that might help put this in perspective.
On the suicide issue, which you highlight, according to This American Life, which did an excellent piece on Apple...
When it comes to the suicide rate at Foxconn, there were about 12 suicides at the Shenzhen plant in 2010. It was actually hard to get the exact number. Some people have pointed out that 12 suicides for 400,000 workers is actually much lower than China's suicide rate as a whole, as China has an unusually high suicide rate of 22 suicides per year per 100,000 people. That would work out to 88 suicides for 400,000 workers. Mike Daisey points out that we don't actually know if these were the only suicides at Foxconn.
Also, it's important to know that many Chinese say working conditions at Foxconn are far superior to those at other suppliers and certainly better than working in the countryside. That's sad, but nevertheless true. See, for example, this recently blog post from The Atlantic which quotes Paul Krugman, among others, on sweatshops.
Again, I say this not to excuse Apple or Foxconn but to provide context.