So I was watching the anime again and I came across this Image... I speculate that this is a bit of forshadowing either his role OR Sauske's role in the rest of the story. I'm personally taking the side of Itachi talking about Sauske eventually taking down himself. For some reason a small part of me thinks that he's still undercover and getting ready to strike against Akatsuki. Perhaps Itachi is the informant to Jiriya. We know there is somone on the inside... We also have this quote! Did he kill his entire clan because he didn't like them? Definately not. Did he do it to make himself stronger??? I don't think so. So why then? To make Sauske stronger.