The Tribune has the dimensions, and an analysis of what it takes to run a board like this.
It doesn't really get into the pros and cons, except to note that it won't cause more noise for the neighborhood. I've never been concerned about the neighborhood, myself. Unless they moved there in 1913, they should have known what they were getting into.
I'm more concerned about the in-stadium experience. I'm still torn on this. My seats will look directly at this new video board. I'm still processing whether that's a pro or a con.