I personally am not a fan of Smart Boards. I can remember spending a large amount of time trying to calibrate the board because the writing was completely off center or the Smart Board would not register our touch. We would spend a large amount of the class time trying to figure out how to work the Smart Boards, but it ended up taking a lot of time up. I think Smart Boards have become more efficient over the past few years, but I think there are a lot of complications with focusing and calibration which takes up time that could be used to productive teaching.
The one thing that I think the Smart Boards are good for is using them to show videos in class. This way the whole class can watch together on the screen and can use other apps as a class! This can include students in the class to come up and click on certain apps to work together! This creates a classroom dynamic that includes all the students to work together! You cannot do these activities on a white board, so a Smart Board would definitely come in handy for these instances.