In terms of influence, it's disappointing that the author neglected to mention the considerable online fandom around the show during its original run. A television show with a genuine series-long narrative arc screamed out for debate over cryptic hints and plot twists, which all found their home within a handful of usenet groups.

And the definitive online reference to the show, The Lurker's Guide to Babylon 5, is still there, unchanged since the mid 90s: http://www.midwinter.com/lurk/