That looks really interesting. I found the example on the features page helpful:
To give you an example, I’ve linked this web page to its markdown file in SVN. I can instantly navigate between these two documents. I don’t need to use the Finder or Spotlight to get from this web page to the file on my Mac. While I am in a web browser on this web page, I just bring up the Hook window. It shows me a link to the markdown file on my Mac. I enter that link and it opens in BBEdit (my text editor), and I am off to the races. That means I don’t need to remember where this file is stored in SVN. Nor do I need to remember its name.
If I could link a Word doc on a network share, an OmniFocus project, an email and a coding environment…