While I'm not exactly sure how the implementation of this would look. My main concern with the concept is that it shares the same issue that a lot of location-based services have.
They create interesting new opportunities for interaction - but they aren't solving a specific ongoing need the person has.
For example, in the video you mentioned people aren't very interested in small talk - but is it a problem they are looking to solve?
It's important for people to be motivated to seek out your app and most importantly use it.
The pictures of a notebook show some creativity, but in the end I think it hurts you more than it helps you. There were some parts I couldn't read well, and writing words on scraps of paper really didn't convey too much about your product (I kept thinking, "what does scraps of paper have to do with meeting people?". Also, by writing down the text, you invite "reading off a PowerPoint syndrome"--show me the story, not the text.
They create interesting new opportunities for interaction - but they aren't solving a specific ongoing need the person has.
For example, in the video you mentioned people aren't very interested in small talk - but is it a problem they are looking to solve?
It's important for people to be motivated to seek out your app and most importantly use it.