Do you want the logical explanation or the irrational conspiracy theory based one?

The logical explanation is that these were all people who lead lives that weren't exactly easy on the mind and body, and a rash of sudden deaths is a slightly surprising coincidence at best.

The crazy explanation is that it's all a ploy to take our attentions off the shitty economy and global situation because nothing makes Americans ignore far more important things than celebrity deaths.

They both have their own merits. Lately I've been in a cynical shitty mood (I work for the bankruptcy police essentially so I have a very rewarding and very depressing job) so I could go either way depending the situation.