I apologize in advance for leaving out many Excel sites that are simply fantastic and are run by fantastic people. My intent here is to list what I consider to be the best Excel sites out there in each category. Feel free to add your own favorite sites in the comments.
The best Excel formula site is:
The best Excel blog site is:
The best “heritage” Excel site is:
http://www.cpearson.com/Excel/MainPage.aspx
The best Excel PowerPivot site is:
The best Excel PowerPivot DAX site is:
The best Excel training site is:
The best Excel charting site is:
The best Excel Power Query site is:
Excel For You 
I really like http://spreadsheetpro.net personally
You are doing a good job with this web site, and I am happy that you like it, since it is yours.
You forgot
1) Daniel Ferry from Excel.Hero
http://www.excelhero.com/blog/
Download everything that’s on it before it disappears
2) Ivan F Moala
http://xcelfiles.com/
Its dead – but you can still access it form the wayback machine
Have downloaded the great stuff from excelhero long ago. He is a modern-day Stephen Bullen. Thanks for contributing your favorites.