On: What one thing does this app need for you to dump Visio for it?

[znt]

This is a very good app. Will you support multi-user editing too?

[davidmxgraph → znt]

Yup, it's in development. You'll have a URL shown at the top of the screen that if you share with another user you'll both have each other's edits in real-time. That'll be out by end of March.