Every summer a cardinal perches on a branch outside of my computer room, and repeatively flies into the large glass window. This doesn't kill the bird, it has been back every summer, to do the same thing for at least a week before it dissapears again. After so long all of the family has gotten used to it, but it still freaks out the cats. Whichever one of our three housecats kill it first is going to get treats.
But anyhow, nobody has died anything soon, and it doesn't look like anybody will. There hasn't even been a death of a relative. As freaky and superstitious as it may be, I think it's a fairly common occurance, especially during the seasons when you have a lot of songbirds in your area.