Jaden Smith is not dead. This hoax could have been a promotion for his new series, but most likely it is a journalist trying to get more attention than they deserve. On the other hand, Jaden Smith is a ridiculous, untalented child who is using his father to further his career, a death hoax is likely to help!
No, I believe that Jaden Smith's "death" is not a promotion for his new series. One of the hallmarks of Smith's brand is his use of his Twitter feed. However, Smith has not tweeted since August 10, meaning that it is possible something happened to him. Although I don't believe that Smith is legitimately dead, I do believe that he may be unwell.
I don't know who spreads these celebrity death rumors. Since this was a fake suicide, it's pretty bad. I can't imagine this type of publicity would be good for a new series. Plus the fake suicide seems to be associated with spam websites, so if it was a publicity stunt, you'd think it wouldn't be.
These hoaxes are constantly being floated on the internet. There is no rhyme or reason to it. I truly don't believe Jaden Smith would have spoken death into his life for any reason, especially something so trivial as a new series. This kid is already rich and privileged. He wants for nothing.