If you though the iPhone was big in China, think again. Gartner says that despite landing a deal with China Telecom, Apple has only a third of Samsung's smartphone market share. Samsung currently holds 24.3%, while Apple currently commands 7.5% of Chinese smartphone owners. Gartner says that the situation won't change without support for China Mobile, the biggest carrier in the country (and the world, for that matter).
As is, Apple will be able to reach 34% of the Chinese market, leaving about 655 million consumers outside of their reach. Even without official support, 15 million China Mobile subscribers are apparently willing to live on 2G and Wi-Fi so long as they get to use an iPhone 4S.
Although it's unfortunate for Apple that they're missing out, they haven't bothered to make an AWS-compatible iPhone to address the entire U.S. market, so it's not entirely surprising that they aren't willing to make a TD-SCDMA iPhone either. Maybe once China rolls out LTE Apple will be able to address the entire market there.
Yes, Apple is still dominating in global profit share, but with Apple's margins, every point of market share brings with it a huge amount of profit share, and in China they're just not exploiting it to its full potential yet.