Oh, and being able to hide checked items in the web version - if this is possible, I haven't figured it out yet, and it really makes it hard to manage a list that's been around for awhile with a lot of already-completed items.

Agreed - I love the simplicity of CF Outliner, but would really love to see the web version developed a little more. I'd like to see things like deleting individual tasks made easier, for instance, so that I can remove a number of things from a checklist with fewer clicks. Keep up the great work CF!