That's quite an oversimplification. I'm not sure anyone has gone full fanboy over JUST a trailer. Most times, and I'll admit guilt here, the trailer is the money shot for months of optimism based on casting, articles, predictions etc. Nobody can be sure of anything till they plunk down their 12+ bucks. But that's the game isn't it? You have to get excited about something in this life. As far as Comicon, have you ever been? Yeah, its basically a sales fest for whatever the studios decide is the big ticket item...but, I've been going for years...and its a blast every time. Sure, waiting in line...not getting into everything...huge crowds...but its more than that. Maybe its mass hypnosis, but there's a reason why its such a hard ticket.
As far as sequels go...there is also a reason the market is flooded with them. People will go try something they have familiarity with. We are creatures of habit. That's part of the reason I try to give as much info on these pages about new stuff. Its like I always say, at the end of the day...vote with your wallet. You want to see more original stuff...the best way to encourage that is by spending your money on a movie that may be unfamiliar, and may not have the calculated budget of a tentpole blockbuster... Some of these movies may not pay off, but its the only way to get the attention of the studios. By the way, not all sequels need to be painted with the same broad brush. For example, the Planet of the Apes flicks have been terrific additions to the franchise. Its all relative, and you have to realize, the big money goes to the safe, calculated, lowest common denominator. The Transformer movies may blow...but until they stop making money, they are gonna keep coming. Its a sad fact of life. VOTE WITH YOUR WALLET!!!