Well, I'll just say it plain: People can be utter dicks, so I'd say inherently evil, but can definitely tend toward good. Lets face it, we all know that, sometimes, hell, most of the time it's easier to be an asshole in a situation, unless you've essentially conditioned yourself to be more inherently good and kind.
Now, that isn't to say there isn't a great capacity for good or even greatness in humanity. Its just that, more often than not, it's easier to be a total dick.
The internet, in fact, is a great example. When you take away the chance for physical, or even simply emotional or mental consequences, people are drawn all the more towards general dickery. It's a word. Internet trolls embody this perfectly.
Anyway, to be honest, I'm pretty damn sure that that's colored by my general dislike for people as a whole (I am a misanthrope after all), but I won't deny that there can be some pretty damn awesome individuals out there. There are. I just wish I met them more often.