It's Super Smash bros. With guns. Yay!
In Small Arms, you attempt to shoot the crap out of your enemies with a variety of guns and your fists. the game holds up okay playing alone, but it is much more fun when you're shooting your friends too. the controls are basic accept certain controls are used multiple times so you might find it confusing until you find what suits you the best.
Visually, the game looks pretty damn good. fire spews out of flame throwers, smoke spawns from explosive shells and all the levels are quirky and interesting for a budget type game.
If you have multiple controllers and friends, or Xbox Live, you will find yourself playing this game a bit. it is a good distraction from the largly played, expensive, high profile games like Gears of War and Oblivion.