Hmmm, I'm still new in the scheme of things but it never occurred to me that things disappear after 7 days, I did wonder why some tags that have great contests associated with them have only the last weeks posts, as though the contest didn't exist prior to then but it's #24 contest... As I said explains a lot.
Also thanks for the links to your Incredible You! series, I have bookmarked it and will work my way through them, I am starting with The The Amazing Power Of Boredom.