It depends on the kind of practice you have. If you are in house, probably not. If you practice in any other area, you should spend some time on social media, but you must do so in an intelligent, targeted way. I've brought in many clients and increased my notoriety through social media. The more you say the more you are considered a "thought leader" because you are in front of people. If you say reasonably intelligent things, people will view you as a resource person. Now social media isn't a panacea, but it can prove quite useful if done in conjunction with other efforts such as good legal work, being out in the community and speaking.
The takeaway: keep yourself in front of people.