Last Sunday, the First Presidency asked that a letter be read in sacrament meeting. It cautioned members not to use visual aids in sacrament meeting talks and to refrain from asking the congregation to follow along in their scriptures. My guess is they didn't want the meetings to become too informal, just as they also try to keep the meetings from becoming too ceremonial.
Keeping sacrament meetings sober, but not somber, can be tricky. Not long ago an investigator approached my brother after a sacrament meeting and said, "That was nice. Do Mormons also have meetings that are spiritual?"