So, the 787 is presumably safer than a 707, and we flew in those. On the other hand, I'm in New Zealand, so any flight I'm likely to take involves 3 hours or more over water; and I still remember going through all the reasons why ETOPS was just fine, the first time I flew Los Angeles to Auckland on a 777--going through those reasons about once every half an hour, actually. (I'm nervous--so? They're not advertising airline travel as an adventure experience.)
At the moment, if I had a choice, I wouldn't fly 787, because although it doubtless does have some advantages for passengers (especially, in my case, the chance to avoid Los Angeles International Airport and fly straight to somewhere civilised like Chicago), it does not yet have an established safety record, whereas we know how good the 777 and the dear old 747 are.
Yes it's irrational. Especially as I was thinking of flying on a 380 just to experience it, before that aircraft had a much more dangerous in-flight event than anything that has happened to the 787. But a very great part of all human life is irrational. Expressing a preference is not the same as justifying it.