This has been happening in other US cities as well, and probably on the same scale. Several realtors I know in the Dallas/Ft Worth area have noted the same things - a large uptick in Chinese homebuyers over the past few years, often with all cash offers. Another friend sold her house, and the person that bid over their asking price and bought it <i>cash</i> and sight unseen? Chinese. They bought it so their daughter and son in law could live there while she attends TCU.
I was in Vancouver last weekend and, as is my habit, checked out the prices near the place I was staying. Houses that I would expect to cost $600k in Seattle were listed at $2 million. I'm still struggling to comprehend that.