...Something is not right, as somone else already hinted.
That killing Intent, thus far the only person we have seen display a paralyzing killing intent is Orochimaru. Sasuke not even wanting to kill the lowly annoyances that cross his path.. somthing is not right.
The 2 theories supplied thus far that can even work are;
Sasuke having the ability to release a bit of the subdued traits and personality of Orochimaru.
or
Orochimaru isnt going out like the way he was portrayed to have.( he either knows he cannot over take Sasuke will as it is or Oro is consciousness has bubbled to the surface and he is hiding it for one reason or another- so Sasuske doesn't work on some countermeasure to totally suppress him)
Or perhaps Sasuke is more than any of us have calculated/read thus far... One thing i do speculate is he cant kill Itachi as he could not even kill a sickly Orochimaru. His eyes can do nothing about the mange sharingan...