If you are number one or two in your industry, you risk sending some of your traffic to the com/net heirarchy above you. Otherwise, just like any land based business, there is room for many players. Think of it like a Pizza shop. Every town probably has a single best traffic place to put a pizza shop with one doing well there. However, there are pizza shops all over town that do good business and survive if they find a niche and serve it well. The .biz is kind of like the neighborhood pizza shop that couldn't get or afford a location on the main drag of town, but still can successfully do business.