The difference is doing it right around the big anniversary of the event. I do think it's in bad taste

I think that the website itself is really cool, and I'm not opposed to using this as a plot point in the story, but using the 50th anniversary of a major American tragedy to kickstart marketing for your X-Men movie is in poor taste.

The timing is the point.

Everyone is thinking about JFK right now, it's the anniversary, History/Discovery/every station under the sun is running some sort of documentary/special/conspiracy theory doc of some sort about the assassination, museums are going ape shit with it. Of course they would do it now. They do it any other time and it gets swept under the rug and forgotten, like all of those other ones you had to go look up.

Because a History Channel documentary about Kennedy's death is about Kennedy's death, and not selling a fucking superhero movie? It's the difference between publishing a book about Kennedy on the anniversary of his death and getting an impersonator to ride in the presidential motorcade through Dealey Plaza in order to pitch a breakfast cereal on the anniversary of his death.

I mean, I think they got screwed because their movie is coming out next summer. Now's the time to start this viral marketing. And apparently this has been an aspect of the film's story for a while. It just feels scummy.

It's exactly like that example. The difference is that the History Channel is (ostensibly) trying to educate you about the event.

The difference between all of your examples and this X-Men thing is that they're all ABOUT JFK. Kennedy is the focus of all those documentaries and books. But not here. The focus here is a superhero movie.

And again, I'm not entirely opposed to using this as a plot point. It's just that using the 50th anniversary of Kennedy's death to launch the marketing for an X-Men movie is wholly different than using that anniversary to launch a book or movie that is ABOUT Kennedy.

I'd suggest those of us outside of a country whose history is being used for fiction are far less sensitive to it.

This.

I'd say the 50th is less important than the 49th which is less important than the 48th, etc.  The 50th anniversary stuff is an arbitraty number that society has decided to make falsely important.  In reality if we actually cared then we would still care as much on the 49th and the 51st anniversary and not only then, but the rest of the year as well.  My dad passed away a few years back and I miss him almost every day, but not any more on his birthday or the anniversary of the day that he died.  Anniversaries make sense from a programming perspective and so does this ad campaign.

Given the fact that there is still information that has not been released to the public, and that there is still questions regarding JFK's death, I can understand the public interest.

Anniversaries are important to people, especially 50 years, which usually considered the half-way (or past half-way) point of a human's life, so it takes on significance of its own in relationship to the human lifespan. 50 years is actually a milestone in many ways.

I don't think anniversaries are a matter of missing more so much as a call to remembrance of sacrifice and loss. JFK is still significant because there are people who do remember it, to whom it was a significant moment in their lives, and brings back both memories and questions.

I don't think the significance or the poor taste of the marketing should be underestimated.