It would be great to have a better keyboard interface for playing/pausing and leaving a lot of comments. I would suggest that when you start typing in the comment box that playback stops and when you ctrl+enter, playback resumes so you don't have to do a complex shortcut or use the mouse. Currently I am shift+tabbing away from the comment box, hitting k, tabbing back to the comment box and leaving a note. This is a simple enhancement that would go a long way.