Quote Originally Posted by DB_Hunter
How's this for a twist. That poke is a coded message for Sasuke to realise that Itachi has been acting all along. Upon this realisation, Sasuke then proceeds to fight the snake/what remains of Oro to save Itachi.
If the poke means anything, it's that Itachi still thinks Sasuke is weak. The poke was always a symbol for plucking out Sasuke's eyes once Sasuke is strong enough and has the Magnekyou Sharingan. Yes, this makes those early chapters more fucked up.