"Our transparency in supplier responsibility is an example of recognizing that the more transparent we are, the bigger difference we would make. We want to be as innovative with supply responsibility as we are with our products. That’s a high bar. The more transparent we are, the more it’s in the public space. The more it’s in the public space, the more other companies will decide to do something similar. And the more everybody does it, the better everything gets.
It’s a recognition that we need to be supersecretive in one part about our products and our road maps. But there are other areas where we will be completely transparent so we can make the biggest difference."
[1] http://www.businessweek.com/printer/articles/85170-tim-cooks...
Similar to when Gmail came out and people were blown away that they offered 100MB of storage, and everyone (Yahoo, Hotmail) had to step up despite their far larger userbase. Then, when they finally matched Google, Google raised their cap to 1GB.
In this case, manufacturers will have to work hard to match Apple's bring-mfg-to-the-US actions, but won't even be on the same playing field, since Apple's worked so hard to maximize the efficiency of their supply chain.