Google flu trends

This is just plain cool: go to and you can see predictions of flu activity in your state.  Apparently Google’s data maps closely to CDC data, but tends to be 2 weeks ahead of the CDC.

How do they do it?  Google uses a model of search term activity to get the data.

Some thoughts:

1. Wow – where else could this be applied, and what else could we learn?

2. Google takes seriously its mission of “organizing the world’s information” – it’s a lot more than search

3. Do you get the impression that Google spends a lot of time doing a lot of things that have nothing to do with what people think of as Google’s “main” business (search and online ads)?