I can see where Jing would be beneficial in illustrating or further clarifying information. Some students need visual representation to refer to when learning new information. The fact that the icon is always visible makes it readily available. I like the fact that there is no need to go to a different site to access it.
Skype makes visual representations available also. I used Skype recently when my father was in the hospital. My friend and I were able to discuss our blogs while talking to each other. We utilized the chat feature when my dad went to sleep. Since I am a Resource teacher and not always with some of my students- I can see where my students could Skype me from the class room at designated times when they needed assistance. This would be an agreed upon time where I would be available.