I noticed those in previous pictures as well and was wondering if it was still going to be installed.
Went to the open house today, looks like these will be signage boards (not electronic ribbon boards) to count the consecutive sell-outs for Memorial Stadium and academic all-americans. They removed the old banners from on top of the north stadium. They also placed an "N" at the 50 yard line. (The signage boards don't stretch the length of the club level deck.)