Later, when I became a free-lance BI developer, I shared this concept with QlikTech R&D but got no answer at all, so I decided to forget about it.
3 years later, nowadays, it looks like the concept is still viable. Here it is:
Make it full screen for better viewing.
Can someone give me $5mln to make it live? :)
PS. Big Corporate Performance Management vendors like Cognos, BusinessObjects or SAS are closer to such kind of knowledge management than pure dataviz companies like QlikTech or Tableau (yet, QlikTech recently introduced annotations in QV11). May be it's a matter of maturity.
PPS. The concept inspired me to create Explainum -- a web service of commentable and embeddable web-charts. However, idea of annotations inside charts hasn't sparked much interest in general public and now Explainum is mainly used for embedding Google Analytics stats (like that one in the footer of this blog).