Gaming has brought me, my friends and my family closer together over the years, it's satiated my aggressions, increased my hand eye co-ordination, introduced me to great people, places and opportunities and has shown me the career path I want to take.
On the other side of the spectrum When I played WoW I would sometimes have very sore wrists, apart from that the only gaming related injury I can think of is when me and some other mates christened our friends new Wii (Back in the glory days, he traded it, bought a 360 and hasn't looked back) by playing Brawl straight for 8 hours, the longest gaming streak I've had. Needless to say the next day I felt like shit (It's brawl we're talking about, squinting your eyes so you can watch the speck of a character you control participate in shiny, flashing and colourful actions).