So David Brandon said that we might have new scoreboards next year. (http://detnews.com/article/20101212/SPORTS0201/12120344/1131/rss17) According to his statements, the new scoreboards he envisions will be "30-40% larger" and the "vast majority" of them would be the HD video screen.
Wondering what this would look like, I decided to do a little research. According to the University, the current scoreboards are 48' x 70' (3360 square feet), with 24' x 32' video screens (768 square feet.) (http://bentley.umich.edu/athdept/stadium/stadtext/stad1998.htm)
I did some calculations based on the "40% bigger" number, and came up with the size of the new scoreboards to be 47' x 92' (4368 square feet.) This is a pretty massive increase in size, especially considering that nearly all of that would be an HD video screen. Basically, picture an HD screen as big as the current scoreboards plus 1,000 additional square feet... The increase in size from our current video screens to the new ones would be 568%.
My projection puts us at #7 on the list of scoreboards by size. Texas is still almost twice as big as that. (http://en.wikipedia.org/wiki/List_of_largest_scoreboards_in_NCAA_college...)