I think one of the things that makes LOST such a good show IS the gray area between "good" and "evil."
It is compelling when the 'good' people do bad things...maybe for the right reason, maybe not. And likewise, sometimes the 'bad' people do things but their reasons are justified...maybe for the greater good.
I really thought Ben was truly one of the 'good guys' but now I'm not so sure. When he shot Locke, we started to see a little of the spoiled, possessive Ben. He seemed to do it solely because Locke was able to communicate with Jacob. Either Ben wanted that power only for himself, or he was afraid that Locke would find out something. Either way, in my head he stepped on the line of maybe NOT being justified for the greater good.
In "The Other Woman" when he got possessive over Juliet, he stepped over that line. There is something noble about doing bad things for the right reasons. Jealousy and manipulation to the point of sending someone to their death (Goodwin, presumably) just so you can have a woman all to yourself...now that is not noble. It's evil.
So far, other than Widmore being a protective father, I have not seen anything really compelling making him out to be pure evil. Okay, so we saw him beating up someone...but we don't know WHY. His motives could be 'for the greater good.'
I for one am hoping that we find out that Widmore is the one that clued Penny in on Desmond's whereabouts. Like, maybe he isn't so bad.