This article does a good job of expressing why I regularly use Twitter professionally. I am connected to people and ideas that I would not encounter without this service. Because of this, I have the ability to push myself and continually grow as an educator. If you are not tapping into this rich resource for learning, what is stopping you?
Professional isolation is a choice given the amount of resources available through Twitter and other resources. If Twitter is not of interest to you, then intentionally seek out personal learning and growth. This is essential for staying relevant in 21st century learning.