I found the definition of "bulletin" from Answers: bulletin: West's Encyclopedia of American Law (Full Article) from Answers.com,
2. A brief update or summary of current news, as on television or radio or in a newspaper.
Why "as on"? Why isn't "as in"?
You see and hear things ON TV.
You hear things ON the radio.
You read things IN the newspaper.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.