I completely agree with your point. Normally, it would be up to the reporters to verify this info. With Twitter and such we can go right to the sources which means we have more of a responsibility to verify what we read on our own instead of taking it as fact.
Although we have none of the tools those reporters do. We're not on the scene. We're not asking questions of those immediate sources (we don't even know if they are truly eye-witnesses...)
Proper journalism is a complex thing requiring a lot more time, effort, and money than I have for every news story. Looking at the hysteria generated by the 'reporting' on various Social Media networks in Iran.... I'm confident that very few people have those things as well.
There is value in journalism, and we are seeing exactly what that is now. Forming truly informed opinions based on social media is nearly impossible. You're better off reading the national enquirer really.