I've been told by a few mathematicians that the article itself is rather nastily written -- the interviewed parties shows people at their worst and often out of context. In addition to portraying certain people (notably Yau) in a rather negative light, the entire mathematics community is depicted as petty and argumentative. As such, the article is not taken seriously in much of the math community. People have their flaws, of course, but things have been taken to rather an extreme in this article.

Does the article take them to an extreme, or is the article accurately reflecting an extreme case?

The article takes things to an extreme, most likely to make a more 'compelling' story to read.

I read this years ago when it came out, and was extremely disgusted with the chinese mathematicians involved.

I don't understand topology nearly well enough to understand Perelman's proof, but many mathematicians who do agree that his proof was correct and complete. Then the Chinese (Yau, Zhu, and Cao et al.) came along, and wrote his proof out more explicitly, and tried to claim all (or at least the lion's share) of credit.

By the way, one of the authors of this article is the author of the well-known book A Beautiful Mind.