I think big name entertainment franchises in general are all falling into the bad habit of trying to please EVERYONE instead of just being happy catering to their niche markets. Plus I think new technology is partly to blame too because it becomes more about cutting edge special effects. I think movie technology will probably level out at some point and it will once again be about what you do with things than how new and fancy they are.
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They need better writers. I can't remember the last time I was surprised by the ending of a Trek, or when the "delemma" presented wasn't something that a five year old child couldn't figure out in five minutes. BUt some content in those shows, and people will watch. Trek is pretty much the scifi equivelent on McDonalds -- nothing worth bothering with.