Audio-only chat would be nice - we use skype, and audio only is our default. If there was a way to make the notes area be a code editor, or have two tabs - one for notes, one for code, that would be really nice. We use google docs a lot, but its terrible for code, so sometimes we use collabedit. Finally, it would be really nice if the notes/todos could integrate with something like an issue tracker or project management tool.
I second pretty much everything in here.In my meeting we were essentially working together grooming a github issue- I could imagine that issue being addable as a tab behind or instead of the notepad.