Mormon Times has a short, but good, article about how the Church has changed as media has changed. There is a link to a lengthy document (113 pages) by Associate Professor Sherry Baker that covers the period from 1827 to 2007. It covers printing the Book of Mormon, to creating a temple video, to using the Internet.
The timeline focuses on technological and organizational developments rather than on what is written or broadcast in the media. It charts the church’s adoption of new technologies including telegraph, film, radio, television and Internet. It also looks at the introduction of church-produced media such as Mormon Tabernacle Choir broadcasts, Web sites like FamilySearch and the beginnings and endings of church newspapers and magazines. She also notes major events that received extensive coverage by non-Mormon media.
I haven’t had time to read the entire thing, but I’ve skimmed over it, and it looks very interesting.