Have you played any of the Geneforge series? Spectactular games, imo, with a really solid morality to it as well. Ultima IV I felt forced into 'virtues' and what not, and it all seemed a touch simplistic. Geneforge though, has let choose morality, but without making ersorting to the kind of Lawful Good vs Chaotic Evil thing you get in a lot of RPGs. The thing I like best is that there are often a few axis of morality at work, usually Control vs Freedom and Responsiblity vs Power. So you can stand up for the rights of the serviles, but still end up a power-mad psychopath, or you can treat them as naught but slaves to do your bidding, but still stand up to the irresponsible use of your powers.
These shades of morality, and the ability to take moral action while following an immoral course, make for a great gaming experience - especially because the choices occur in the context of such a richly fleshed out world and culture (for a Computer RPG, for sure).
I think that, yeah, simply imposing a moral system on a game is a terrible idea. Games in which a pre-defined set of 'bad' actions always have a negative effect, and vie cersa for 'good' actions, are often preachy, patronising, and boring.
That said, I do worry equally about games like GTA, in which bad actions rarely ever have negative consequences, and good ones rarely have positive consequences - and the cases in which they do are mainly in cinematic parts where the player is not making a choice.
The best way i think to handle it, which is done in the Geneforge series, and a bit in Fallout as well, is that, like in life, both ethical and unethical actions will sometimes result in immediate rewards or penalties, as well as long term rewards or penalties, depending on the situation and the characters affected. As in life, you can profit from good or profit from evil, in different ways, so you can play the game however you want. Then at the end (and don't get me wrong, I'm an athiest) your choices all come back to haunt you, as they dictate which of the myriad of endings you get, and you get the satisfaction of seeing the consequences of your actions.
For me, Fallout and Geneforge will always have something over even the most sophisticated MMO that lacks the scope for moral choice at that kind of level. It's failing to capture an important element of stories, and failing to engage a vital element of what makes us humans.
