Proposal for notes

@cheddar -- thoughts?
The thing I fear with (2) is that the only way to code such that even if it were to happen, it wouldn't be an issue would be to code it to do (1).

On the pitfalls of (1), I agree, but as I stated below when talking about the `time` field, I think we need to colocate messages by time anyway ('cause even when you see this field is set, you are still going to have to go in and load all notes for all time in order to try to find the message that links with this one).  The other option is to have the child pointer and just follow those...

I guess I'm saying that I'm gonna hold off on any more conversation about this issue until we discuss the `time` comments, 'cause I think those are going to affect this.