Some nodes have bonuses like XP, Credits, Stop Worms and Nukes. Before hacking, on the hacking screen press select to see the meaning of each icons.
What i wish for is for a game like this to have a 3rd person view option, why in hell a game like this have to be 1st person in the first place. Also for God sakes! sometimes I feel the need to kill a guard because the animation is much more cooler than knocking them down, why in hell everybody automatically gets hostile even when nobody saw me killing him, that is really stupid as hell and it kills the fun.