http://manual.calibre-ebook.com/index.html
I was wandering if you might consider adding a last updated date to the calibre User Manual. Yes, I am reading and I suppose studying the user manual. I think your software is amazing!
It would be nice to know when there is an updated manual to download.
An ebook version of this user manual is available in EPUB format, AZW3 (Kindle Fire) format and PDF format. Last update: 04/26/2013 
Thank you for this consideration.
Awesome software!