It's an MMO where you are a spaceship captain. You train skills, get bigger ships, mine asteroids, form corporations or conduct wars or hunt pirates or be a pirate, whatever direction you want to go with it.
Played it for a while. It is definitly different from Everquest, WoW and other MMOs like them.
It's nice and non twitchy for the most part, but I did encounter so far one player who is a player killer and preys on newbs. I'm not sure how common that is
Extremely.
and of course the boards on the topic are dominated by the hard core players who insist that it is not a problem
That depens on what you'd call a problem.
or simply a part of the game
this.
and a way to keep out the non-serious players. Any experience?
Well there's one useful bit of info you already got: it's a game for "serious" gamers. Now, there's no real point in talking about constant grinding and repetitive boring stuff, all MMOs include that, Eve is no exception.
A few noticable differences are: You "level" by waiting. Seriously. There is pretty much nothing you can do to make your character progress. You assign a skill to learn, and it will simply be learned, over time wether you're logged in or not. Your attributes make this go faster and you can buy attribute upgrade, but that's maxed out pretty quickly. So, after a few weeks of playing, your character progresses pretty much without you. Some players might like it, i think it takes much of the point out of a RPG.
Eve gets called "by griefers for griefers". Which is pretty accurate. Preying on newbs is allowed. Encouraged actually. Think of it as a constant, no-rules, free-for-all PvP game. The only people you can trust are the ones in your corporation (guild/clan) and even there it's been known to happen that people took months to infiltrate a corp and get access to accounts and steal everything and disappear.
The interesting part of the game is corp vs. corp fighting, which the game is pretty well suited for. Though you can expect the "serious players" in the serious corp to make serious demands of your time.
Since the game is free to DL though, and you can play the trial for a while (iirc two weeks) i recommend just trying it out.