So you’re in another app and you want to make a note. You can use the service, but which document will that go to? Also, what if you want to make changes to the note’s content as you save it, like add a title or tags?
Well, you hit your hotkey and bring up Quick Entry.

Pick the right document, enter the information (the tags even auto-complete based on the selected document), and either clear it (for temporary scratch space) or save it to the document and it will auto-clear for the next note.