Two reasons. First off, Americans (and I'm one so I can have an opinion) are trend whores. Quality matters not in the face of what's considered "cool". MS, being an American company, knew this better than anyone. They worked really hard with marketing the original Xbox and Xbox live in such a way as to come off as the "cool" console. If you watch the original Xbox Live adds, they use catch phrases like "trash talk with opponents" and "throw down on Xbox Live" bla bla bla. They appealed directly to the American senses, and it paid off.
The second is because early on, they focused HARD on online gameplay. American's were willing, hungry and ready for online gameplay before the rest of the world. So, naturally, the 360 appealed to them in that way as well.







