New Scientist discusses the mystery over Chinese denial of wildfowl flu deaths in its current online issue (subscription required).
The article concisely summarizes the uncertain reports from Boxun and the equally uncertain arrests of Boxun's local volunteer reporters. Until the publication of the genetic sequence of H5N1 from the wildfowl, we won't even know what really hit them. Since such rapid and widespread infection and mortality are unusual with avian flu, it may even be that something else is behind the deaths. The article points out that H5N1 isn't known to exist in India at the moment, and infected wildfowl migrating from India would likely have died before reaching Qinghai.