Definitely not. SEO - this method has been the basement for building a website. What is the main drawback is, you have to wait for a long time to obtain results . SEM - nowadays no one is ready to wait. They need instant result of what they discovered. For this purpose many people started using SEM to start earning quickly. Other than that SEM wont over take SEO.
This post has been edited by RobertWoges: Jun 16 2014, 06:20 AM