Chainsaw battles included in Gears 2
According to this, the chainsaw versus chainsaw battling in the Gears of War 2 teaser trailer wasn't a fanciful thing: it's actually included in the game.
I was talking to two people last night who are close enough to the development team at Epic to know and they confirmed for me that this will be a mechanic in the game: When somebody tries to chainsaw you, there will be a way to push back with your own chainsaw gun and potentially fend them off or, possibly, end up chopping them into a bloody pile of flesh chunks.
Another reason to buy it. If there wasn't reason enough already.