Ali Edwards has been doing this since 2005 (I seem to have missed it each year despite the fact I have been scrapping since 2003!)
So take a look at her thread here about it and see what it is all about and more can be found here.
If you fancy joining in just take a bunch of photos for 7 days and then more will follow on the creative process she promises.
Here is a glimpse at my day 1 yesterday.
Ali Edwards sums up her Monday here. Have fun if you are joining in!