I would say most of the people who do not think video games, especially the online MMORPG variants, to be dangerous to your spiritual well being, either have not experienced or watched it hurt someone else, or are in denial.
We are commanded, for example, to abstain from addictive and damaging substances such as coffee and alcohol. Scientific study has shown that actually drinking small amounts of each, every day can actually help the body. So why are we commanded to abstain? One large reason is that both can create addictive habits, and addiction is slavery.
The same is to be applied to video games. Yes, of course, if we control our selves, and play within limits, we will not be overly damaged as a result. The same is also true of coffee and alcohol. But the fact remains that the majority of MMORPG players spend 6 or more hours a day, often as much as 16 hours a day playing these games.
We are told that it is not well that we should be commanded in all things. We have also been instructed to choose better and best activities over good ones, so even if gaming is not an addictive habit for you personally, there is very little, if anything, to be found in almost any game on the market these days, that could be considered spiritually uplifting.
I know firsthand the damage that MMORPGs especially can do to someone. Fortunately I opened my eyes before the damage was irreparable, but I have lost jobs, neglected family, and had countless fights with my wife as a result of playing MMORPGs. I can garauntee you that there will be no MMORPGs or video games in the celestial kingdom, or in the spirit world for that matter. Now is a time to prepare and to learn. You will have to give up video games at some point, and trust me when I say, it will be so much easier to do so in this life when you are physically able, than it will be in the spirit world when you are not.
Do not kid yourselves. Video Games are not a creation of Godliness, and any good thing that comes out of Video Games are overshadowed a hundred times over by the bad.
It is another tool of Satan in this world to lead away souls to captivity. God does not find delight and entertainment in war. God does not find delight and entertainment in the conquering of rival kingdoms. God does not find delight and entertainment in the idea of slaying animals, monsters or 'bad guys' in a fantasy world.
But even if these are only the backdrops of our desire to create, progress and build, there are other destructive forces at work. The social communities of MMORPGs are akin to a chapter from the Lord of the Flies. They are anarchistic, contentious and filled with vulgarity, swearing, mockery, and almost impossible to maintain the Spirit with for more than a few moments at a time.
Elder Bednar recently wrote about this in a recent Ensign article. He told us that it is Satan's desire that we live in virtual, fantasy worlds, so that we deny the glory that is our physical body. He says that in doing so, it is as if we remained in the spirit world, because we act in a way that denies the sanctity of physical interaction, that being one of the great purposes of us receiving a body.
No, video games are not alone in their power to create compulsive behavior. But our leaders have also warned us about what we watch and how much time we spend watching television. And if compulsive knitting were an epidemic problem in our society you can be assured they would be speaking out against that as well. In the most recent general conference, I heard at least 3 talks alluding to a direct commandment to be wary of video games, not to mention other recently published material such as Elder Bednar's talk. Be honest with yourselves, and put personal pride aside if it is preventing you from feeling the Spirit on this. If you doubt the validity of what I have written, approach Heavenly Father in prayer, and ask, sincerely, if this is true. Certainly if you are spending inordinate amounts of time on video games, I feel confident that I know what the answer will be.
"Therefore, blessed are they who humble themselves without being compelled to be humble".
If it is a Celestial eternity you seek, you will never find it in a video game. Leave it behind now, of your own accord, and be blessed, or be compelled to do so, and suffer for a greater time as a result.