It is actually my business. It started as a side-project but I kept working on it and now I make a decent living from it. So I like I can keep tweaking it to adapt to my personal system and feedback I get :p
Looks like it's exactly what I'm looking for and I love supporting tiny projects, but it's difficult for me to commit without knowing I can get my data out of it easily.
Also, you can use the API but I haven't publicly documented it! Some people use it to do their own stuff with their data :)
It is a work in progress!