The best defence is a strong offence. Said another way, the best companies don't spend too much time looking in the rear-view mirror, and instead focusing on the drive ahead. Most web and mobile businesses are not defensible by true I.P but rather speed of execution, great design, responsive and caring customer support and a relentless concern for the customer. In the case of the example you provided, content quality and regular and timely updates are also key competitive differentiators.