This argument fails on a number of grounds, the least of which is that we may or may not be improving there lives by hiring them to work 85 hour work weeks factories that lack any air conditioning. Perhaps some of these people were starving as farmers, perhaps many of them weren't. Do you have sources that point to the extent of the improvement that factory life is bringing?
Furthermore, do you know that this really is the road to improvement for this generation? You talk as if these factories really are gifts from generous westerners, as if these companies should feel justified, if not proud, that they are transforming and saving the lives of these workers. I recently heard a podcast on Radio West titled, "The Cost of a Two Dollar T-shirt." In it, the author took a non-sensationalist approach that the t-shirt factories in Cambodia really were humane, they were even air conditioned. However, he mentioned that these people still lived in shanty towns and barely made enough money after 60 hours of week to afford food. He also mentioned that their 33 cents an hour wages were lagging behind inflation, and, in fact, these workers were becoming, relatively speaking, poorer and poorer as the years went on. So, no, I disagree with your claim that any factory job + time = helping raise another country out of poverty.
(Link to the podcast I mentioned: http://www.publicbroadcasting.net/kuer/news.newsmain/article...
Also, link to the original article by the guest on the podcast: http://harpers.org/archive/2010/01/0082784)
Lastly, you provide no justification for why the conditions need to be so bad. You seem to be saying that, since these workers were previously living in worse conditions and since we're improving that life, it's justified to either treat them inhumanely or exploit them. Their lives have been improved ergo they either have no right to complain or we have no responsibility or motive to do any better. There is no high road in your argument, only defensive argumentation and justification of labor practices that are well below what they should humanly be.
In the article I linked above, the author mentioned that the labor costs of making a t-shirt for a major corporation (Gap, Nike, Walmart, etc.) only made up 4% of the total cost of the product. If that's the case or even close to the case with the Microsoft factory mentioned in the original article, then going even so far as doubling the worker's wages would have a minimal impact on the bottom line of the product. At the very least, fat could be trimmed from the other 96-ish% of the cost of making the product to make room to improve the factory conditions.
Not only could most corporations afford to improve the wages of these workers, but what is lost by improving the conditions? Wouldn't workers who are sweating for an entire 16 hour shift be happier and more productive if the management spent more money on air conditioning? Even if find proof that happier workers aren't always more productive and perhaps sweatshop conditions really induce more productivity, there needs to be a line, a line of basic worker's rights, that prevents the downward price pressures from a competitive market from creating deplorable working conditions for anyone.
Your arguments seem to suggest that everyone goes through these deplorable factory conditions before they move onto a better life. Not only do they not NEED to go through these conditions, as ultimately someone has the power to change and improve the conditions of the factory, but these workers are not necessarily guaranteed that life will improve afterwards. Perhaps these working conditions become de facto and the workers don't make enough money to earn an education or gain the economic mobility to choose better working conditions. The system could just as easily become entrenched, leaving a class of workers trapped in poor working conditions for generations.
At the base of your arguments, I think it's frightening to ever use relativistic arguments to justify inhumane treatment. Take slavery in early American history: "Well, slaves used to live in malaria-ridden Africa in mud dwellings, and now at least they get a stable source of food and, most of the time, a wood shelter over their head." Deplorable conditions always need to be addressed and justified in present and absolute terms. Inhumane treatment is inhumane treatment, and active steps should always be taken to improve such conditions. The improvements should not be left up to the "benevolent" forces of time or ignored because the conditions are a (slight) improvement over previous conditions. If you're going to offer a poor farmer a job, you don't have the right to offer him a job with any such conditions that you choose.
Sure, I'll grant you that the article was sensationalist (maybe the photographs were taken without needing to be "smuggled out", etc), and I don't think any cause can be constructively advanced when such arguments are used. However, the majority of your arguments are morally objectionable and logically unsound.