No they do silly little shit and it's generally explained, this was basically a confirmation that the picture at least was from the future. I could be wrong, but can anyone come up with another example that was flat out supernatural/sci-fi and not Castle's imagination running before it got explained?
Castle is based in reality. Any suspension of disbelief is normal TV style, not science fiction.
It doesn't ruin the show for me, or even the episode, but it was not at all subtle and does not fit in a show based on reality. Just a very mild annoyance for me if that's all it is. If they run with it though, that could be amazing or terrible but it would be interesting either way.