I never pick up Counter-Strike as a game for a quick 10 minute shoot-out. It's always involved, with friends, something to do for the whole of lunch or evening. I get too involved and the structure of the games made it more of a long slog. Then Counter-Strike: Global Offensive added Arms Race.
It's very simple: two teams start off with the same guns. For every kill, the player instantly recieves a new weapon that replaces the one they have. The weapons cycle around until the player is left with just the knife; the winner is the player who makes the first knife kill.
A couple of things that grabbed me right from the start: no waiting. You die and you respawn in a few seconds. I love CS, but being killed at the start of a round is one of the most frustrating penalties, and the older I get the less inclined I am to hang around and wait for my team to avenge my death or die valiantly in my honour. There's no waiting or watching, here. You die and get right back into it. There's also no buying: you're given a weapon to start off with and you don't have a care in the world, other than who to kill and what your score is. It's oddly liberating.
Which is very un-Counter-Strike, but that's the point. Valve have been trying for years to work something new and interesting into CS, but they've always been sniped: Remember Condition Zero? The single-player game was supposed to be a new beginning for CS, but it proved to be so bad Valve rejigged it, instead refocusing Condition Zero as a traditional game but with added bots. The single-player is nothing more than a curiosity on your Steam account, now.
Arms Race, however, already has its roots in a Counter-Strike mod called "Gun Game", so it's something that's already been absorbed by the prickly community. And it's now the thing I use to make 10 minutes slip past. You really don't play for the team in Arms Race: after the initial spawn, you all spread out and spawn at different times. Sure, you watch each others backs, but usually when I save someone from dying it's a secondary bonus to hopping up to the next level.
The maps needed for the mode are startlingly different from de_dust: compact little arenas, symmetrical so no-one gets an advantage, but open to allow for the wide-range of weapons to be used. My favourite is the multi-level, criss-cross of death, Baggage: if you end up in the lowest section, the bodies of those dying above drop and flop all around. Like all of CS, they're easy to learn but tough to master, and end up in speedy matches. You can die at the spawn and spawn quickly enough to return the favour to your killer.
Which doesn't mean it's not tactical, it's just a different kind of tactical. In one game in on baggage I spotted that a team mate an opposition player were both reduced to knives(everyone has a knife, but the final level is knives only) level. I'd just spawned with a sniper rifle. I'd just spawned with a sniper rifle, so held back and watched for their player: he spawned and was heading to another of my team, who had his back turned. There were easier targets, but I lead him on, watching for his final lunge at my player before popping him in the face. If I hadn't the other team would've won the game.
Got ten minutes to spare? Got a beta key? Give it a shot.