This story has been making the rounds of the internet recently- George Lucas states that Han was never a 'cold blooded killer', and that the scene with Greedo was always intended to play out with Greedo shooting first, then Han. In fact, Lucas now says that there was a wider shot that he didn't use in the final(heh) version that showed this.
To all of this, I say- meh.
I try not to get upset about Star Wars hoopla anymore. I am far past my 'angry fanboy' stage now (for an example of fanboy rage, see my earliest posts on this blog). The only thing that really ticks me off anymore is "The Force Unleashed" franchise.
Whether George is telling the truth about this 'wider shot' or not doesn't change my opinion of the scene as it played out originally:
In the 'real' version of the scene, Greedo takes Han at gunpoint and proceeds to tell him flat out that he's going to kill him. Thus, Han shooting him from beneath the table is an act of self defense- and quite justifiable in any one's eyes. I never for a minute thought "Oooh, Solo is a cold blooded killer!" (though evidently, quite a few others got that...) My thought was. "Yeah, that was pragmatic. The guy says he's going to kill you, so you kill him first. Makes sense to me."
In short, it was again something that didn't need to be 'fixed'.