Pattern recognition is one of the first things that comes to my mind. In order to win a game, you often need to realize how your opponent acts, whether or not they're controlled by the A.I., or by another player. You need to be able to anticipate and counter their next move. This skill not only comes in handy not only when you're fighting a boss in Mega Man, or playing against someone in a fighting game, but in real life sports, and just about any other form of competition.
Expanding one's vocabulary is also an added benefit. And I don't mean learning words related to violence, like "immolate" or "annihilate." By playing games, I've come across countless words that I didn't know the meaning of, and looked them up in the dictionary. I'd even go so far as to say that that's the reason why in elementary school, I was given the nickname of "the human dictionary." Some examples of words I've learned by playing games include charisma, vertigo, nostalgic, ambidextrous, magnanimous, eloquent, sanctity, infantile, addled, dispel, exile, proficiency (I use this word a lot in resumes), exponentially..... I could go on. Hell, some people have even used games to help teach themselves another language!
Multitasking is an important skill in life, especially if you work in a job where you have to research and type information, respond to e-mails regularly, and keep track of things like deadlines. Countless real-time strategy games help to hone that skill by forcing you to make sure your workers are gathering resources, your upgrades are being researched, your base is well-defended against enemy attack, and that you're keeping an eye out for and stopping your enemy's attempts to build auxiliary bases.
Quick reflexes are a huge requirement for many games. Ducking the split-second before a bullet aimed at your head is fired is a common situation among many hardcore first person shooter players. That kind of quick thinking can also save your life when you're driving. There actually has been at least one situation where a driver barely managed to avoid a collision on the highway - which he attributed to the reflexes that he honed by playing games.
http://www.dailymail.co.uk/news/article-1350071/How-driver-miraculously-avoided-motorway-crash-thanks-gaming-skills.html
Critical thinking is also very important. Much like in real life, there are countless situations in games where things don?t go as you planned. You have to then determine the best way to solve the problem. Maybe you need to open a door, but it?s locked and the key?s in a location that you can?t seem to get to. Or maybe you have to defeat an enemy, but none of your attacks seem to have any effect on it.
Countless gamers have fond memories of cooperating with their friends to overcome tough challenges. Whether it's by letting their friend take the pizza because they have less health, or by building an army of tanks to take out a network of enemy anti-air turrets so that an ally's fleet of ships can safely attack the enemy base, many games encourage players to work as a team. And of course, teamwork is an essential skill in countless jobs, sports, and other real-life situations.