I more surprised at the fact that people are touting the high number of Asians at Google as some sort of success story about us Asians and our culture. Google hires people from around the world, not just the US.
I'm more inclined to believe that there are high number of Asians simply because there are more Asians in the world, period.
The races that are obviously not Han (so the western side of the country) don't blend and have many problems. We are going through a bout of terrorism right now for this reason (coupled with Han paternalism, which makes the problems worse).
The races in the east have mostly inter-married and integrated with Han culture, though there are still some tensions (the largest Zhuang minority has been very rebellious up until the 20th century).