Who's he gonna get revenge on for what happened to him? Yeah maybe the guy who set up the bomb, but it's hardly the same as targeting the gang members who horrifically gunned him down in cold blood.
Why does he have to get revenge on someone, just because it happened in the original film?
Good remakes / reboots / re-imaginings / re-whatevers take a concept, that may (Star Trek) or may not (Battlestar Galactica) have been done well in their original incarnations, and do something different with it.
The inclusion of Murphy's wife in the RoboCoppization, for lack of a better term, is a really cool spin on things. The best part of
RoboCop 2 is exploring the body horror that was perpetrated upon Alex Murphy without his knowing consent; this could be a really interesting take, in that at some point he learns that
his wife had him turned into a cyborg.
The other thing to keep in mind is the line, "The illusion of free will." That says
everything about where this film is going, I think: What happens in an authoritarian, "You are free to do as we tell you" society? We're asking ourselves that question today in light of PRISM, drones, secret courts, the PATRIOT Act, etc. It's a very relevant theme, and I have faith in Padilha to really explore it.
Just because it doesn't hit the exact same beats as the original doesn't make it
bad. Go watch the original film if that's what you want. In any event, "Murphy is out for revenge" isn't the central theme of
RoboCop, it's "Murphy regains his humanity." To watch
RoboCop and be all "hell yeah, killer robot goes out for blood" is to
completely miss the point.