Hierarchy of digital communication

It seems like there's a certain hierarchy of digital interpersonal communication. It's almost innate as new technologies become commonplace. Some events warrant a text message but not a phone call or an IM but not an email. This list is by no means exhaustive, but I am at least trying to limit it to interpersonal communication, excluding modes like blogging, conference calls, etc. where there are multiple recipients. I'd actually be curious on how others perceive the order and even additional interpersonal modes to those below. Here's my top down list.

Video Teleconference
Phone Call
Push to talk / walkie-talkie
Email
Instant Message
Text message
Private social network message (facebook message)
Public social network message (facebook wall)