Bpatrick, I think you're right about ABC's Dallas coverage. It was, IMHO, some of the best coverage of the entire period. Imagine an interview with Abraham Zapruder before the world heard of his name! And I'm glad you mention the Smith-Morgan participation, because it so often gets overlooked.
Two interesting things about Cronkite and his place in history: although he has come to be the "face" of television coverage of the assassination, in fact it was NBC's coverage, anchored by Huntley and Brinkley, that dominated the ratings - attracting more viewers than CBS and ABC combined (although, let's be honest, ABC doesn't contribute much on that score). According to Gary Mack, curator of the Sixth Floor Museum here in Dallas, one of the reasons for Cronkite's ubiquity (aside from the very good work he, and CBS, did with their coverage) was that CBS smartly licensed out both the audio and video of their coverage together, making it possible for the dramatic moments to be used as clips on so many shows and documentaries over the years. If anything, NBC's coverage (in which Frank McGee visibly winces at the moment when Robert MacNeil gives him the official announcement of JFK's death) is as dramatic, but it has never caught on in the same way.
The second point about Cronkite is that, although we think of his dominance of television news as inevitable, less than a year later he was replaced by Robert Trout and Roger Mudd for CBS' coverage of the 1964 Democratic Convention, so thoroughly had the network been trounced by NBC. This is not to denigrate Cronkite (although I was always a Huntley/Brinkley man myself); it speaks to his resilience and talent that he eventually rose to be the undisputed face of TV news.
Finally, I would be remiss if I didn't include a link to my recent interview with Marc Ryan, author of "Three Shots Were Fired," a book looking at TV's coverage of the assassination - and, incidentally, son of NBC's Bill Ryan.
http://www.itsabouttv.com/2013/11/interview-marc-ryan-author-of-three.html. Yes, it's a shameless plug for my blog, but I wouldn't share it if I didn't think our readers might not find it interesting and an addition to our discussion on the thread.