Question - When does a game, stop being a game, but becomes part of your life?
The edges are becoming more and more blurred when it comes to gaming and real life. But then again this is nothing that can be blamed solely on the computer age. When Role Playing Games first came out (in particular - Dungeons & Dragons), there were reports of people actually living out their lives as their RPG characters.
Another game that spings to mind is - Steve Jackson's Killer (AKA Assassin, Gotcha, etc). Great game - if you know the boundries - What is real, what is fun and most importantly - When to stop.
http://en.wikipedia.org/wiki/Assassin_(game)
Gaming should be fun - and kept that way. If you try to make it too realistic, then the industry just leaves itself open. There have already been enough cases go through court where killings have been blamed on violent games, and to try and make them more realistic just blurs the edges even more.