An important part of my workflow[1] is similar to this approach. I believe it's got a lot of potential if done right. One concern I have is the lack of file upload support (I only see images) and that querying relies heavily on tags. WRT the latter, it didn't work until I was able to create new projects that only held notes related to a specific project/topic. The current trend of dumping everything into one big database and hoping for the best when it comes to review and retrieval just does not work for me.

[1] Based on what I can tell from the linked page, which doesn't give a ton of detail.