This game has been out there for about 2 years or more, only available at Desura(where it has already got a bit of a fanbase), but now it finally found its way to Steam. It provides players with really unique experience by making them seemingly insignificant - in "RUNNING WITH RIFLES" you are not a chosen one, you are just a soldier, just like the hundreds of others around you. If you think that titles like Call of Duty or Battlefield provide the same experience - you are horribly mistaken; in Battlefield you fight maximum of 32 enemies at a time, while in RWR there can be hundreds of them! So, yes, you will totally be unable to turn the tide of a fight – nobody can defeat 200 hostiles on his own. But don't think that player's actions don't matter at all: you can take charge of a squad, and then you'll become a real threat. Your squadron will still not be able to destroy the enemy forces compleately, but it will deal significant damage by blowing up their vehicles and radars, capturing their fortifications and slowly depleating their reinforcements.
The majority of both players' and opponents teams consists of AI-controlled soldiers. Bots can do everything players can - form squads, drive cars and tanks, take cover, use knives, grenades and sniper rifles. It's worthy of note that AI is really-really good, not as good as a real person, obviousely, but much better than in a lot of other games, even singleplayer ones. It will try to flank you, use every advantage it can - trenches, artillery, vehicles. It acts pretty much like an RTS AI, which makes it smart and quite challenging to deal with.
But what makes the game for me - it's its community. Online players are very friendly, people often cooperate to achieve certain goal; more experienced players always help the newbies to fit in; low-ranked players often execute higher-ranked ones' orders. Even the devs can be found online chatting with the community!
So, if you are looking for something new in Action genre, if you are tired of "standart" shooters and always-angry players constantly yelling at each other, you should totally try "RUNNING WITH RIFLES".
P.S. My apologies for my bad English, which is not that bad, but still no way near perfect. =/