Okay everyone, 
I've got a prediction. 

*THE BOILING ROCK SPOILERS*

In the end of the boiling rock 3 new people are added to the group. Suki, Hakoda, and a mysterious convict of the firenation called Jitsang. 

We don't know much about this character. We know that he was in the boiling rock. The highest security prison in the firenation. Now what exactly did he do to get into there? Maybe he's innocent and was convicted under false charges.

Episode 316 is called "the southern raiders". It is said to be about Katara and Sokka's mother. And Hakodas wife.

Now here's what I'm getting at. Isn't it entirely possible that Jitsang is responsible for the death of Katara's mother? It also makes sense that in 316 we find out that Jitsang is responsible for her death, and that the episode is dedicated to Katara having flashbacks of the day she lost her mother?

Now I am probably forgetting other points I have, but I'll write them in my next blog. 

Please comments with your own opinions.
THANKS