They do have a huge network of personal weather stations that the Weather Channel doesn't have. It's mentioned in the blog post that the Weather Channel was going to start incorporating that data on weather.com.
The real skill in weather seems to be from WeatherBill, now The Climate Corporation:
http://ecorner.stanford.edu/author/david_friedberg
When there is big money on the accuracy of the weather prediction and measurement, they tend to get it right.
It's still sad though. Weather.com doesn't have anything that works as well as the WunderMap, and certainly nothing I can leave running 24/7 in a browser unless I want to restart it every few hours.