As for global awareness – I no longer consume my news from traditional media sources, and Twitter is my source of information. So people changing their avatars is as good for me to point me that something is going on just as a CNN anchor.

The skeptics critique, though, is two parts:

1. Did Twitter users really not know about the Iran election violence? It inundated the media such that if you were missing it, your awareness of the situation probably didn't matter all that much (since you likely lack the deeper interest in global affairs to truly understand the situation).

2. Is the effort put into projects like this (by both creators and users) a displacement of other, more constructive efforts? I'm less convinced of this and think a better explanation is found in a form of social signaling that the green tint or Livestrong bands give off – they are subtle, contextual clues to inform peers that you are socially conscious. The problem is, many of the people doing that aren't – they're just bandwagoners.

I see these “digital actions” as a way to raise awareness to a cause. I got to know about what happens in Iran after I saw two people who tinted their avatars to green manually and I think it's a great way to show people that something happens.

Obviously most of the people won't do anything for the cause beyond tinting their avatar or wearing a wristband, but that's ok – most chances are that they haven't done anything anyway, so at least they're helping others to get to know of the cause.