A citizen journalist (well it means an ordinary guy with a cellphone) takes a video showing violent crackdown on street unrest. Later she sends the video to Youtube, which is linked against her Gmail account. It is not exactly discussing incriminating matters. In fact government cannot arrest people for daily jokes they make about Ahmadinejad, because they may have to put everyone behind bars then.
You are right however, one should take extra precautions. No matter what the odds or reason to be arrested for, it only takes a hard enough blow to head to be considered dead. Together with a transparent proxy, a dummy Gmail account does not waist too much bits and bytes.