Babylon 5 was my favorite SF series, if not of all time at least my favorite to come out of the 90s. My wife and I watched the first broadcast of the pilot movie, "The Gathering", and thought that it had a lot of potential. By the end of the first season, we were hooked, and watched it obsessively. We went to our first big fan convention, Chicago ComiCon in June 1995, because series creator J. Michael Straczynski was going to do a presentation about the show, including promo clips of the "Final 4" Season 2 episodes (which didn't air until October of that year). There were something like 2500-3000 people at that presentation alone (when most Cons are glad to see that many attendees for an entire weekend.)
Aside from the content and format of the show itself being innovative, the B5 fandom was innovative as well, being one of the first to really grow on the Internet of the time. The Usenet group rec.arts.sf.tv.babylon5.moderated had JMS himself participating, and the Lurker's Guide to Bablyon 5 website was famous for doing in-depth reviews of every episode, including speculation based on what JMS said in the Usenet group. It was all great fun. ^-^