Eh, Ultraman fandom isn't going anywhere. Ultraman doesn't have a ton of gimmicks or anti-heroic (or just plain jerkoff) "badasses" or a ton of other characters who can also henshin going on so you won't find much hype about it outside of Ultraman fandom itself. Also the approach to your average Ultraman series is just simply very different from what you would find in a Toei Sentai or Kamen Rider show.
However, this does not mean that Ultra fans are diminishing rapidly. If anything I think it has a slow but sure gain that's come about from people looking for an alternative to sentai and Kamen Rider. People coming to toku fadom are discovering it all the time. I think for every five that might think it's boring there's always a 6th person who wants to see more.
I have no problem with Ultraman myself even though there's only been a couple of series I really got into (Tiga and Nexus) I think basic idea behind Ultraman is awesome and there needs to be a hero who represents the light.
Heh, looking back on it at the time I was checking out Tiga it was kind of nice because I felt like I had a balanced plate going on. For a hero of light Superman vibe I had Ultraman Tiga, for a Batmanish hero fighting for justice in a darker world vibe I had Kamen Rider Black, and for superteam dynamics I had Sentai (I think I was checking out Jetman and MegaRanger at that point.)
I know the shows following Nexus are supposed to be a bit closer to traditional Ultraman which I don't neccessarily mind but I haven't liked the designs and the shows themselves have been a bit too far on the goofy side for me. Still, I'd love to see a show that maybe had a traditional vibe but a more sleek design sense like Nexus or Tiga.
..though I guess Tiga is considered traditional to? Or only sort of removed from tradition? I kind of felt like it was to Ultra what Black is to Rider. Kind of a medium of modern (for then anyway) and classic.
