28 people matched the 10c donation, and there was $8,000 of adhoc donations inspired by the action. See: http://favstar.fm/users/Mike_FTW/status/27901780152
A real test would be something like the protests in Iran. I remember wondering why the regime doesn't just block Twitter, like they do for other sites. Apparently it wasn't worth the bother, the impact was more felt in the Western hyposphere than Iran. Personally what really concerned me was the State Dept asking Twitter to reschedule downtime for this. I'd hope they have somewhat better sources.
People took out their wallets, and paid. See if you can find the 28 people who matched. It's not easy - they're not getting any PR. This was someone who on a whim decided to attempt to raise money for a charity through the Twitter medium, and he gained a lot of support. The trigger was favs, not RTs - I'd argue it's not a PR stunt.
I do share your cynicism about the Iran situation, but I think Twitter can be used as an effective tool around smaller issues as demonstrated.
What if in the future there are 2 billion twitter users instead of 170 million? Do you think there will generally be higher awareness of global issues? Before you can act on something you need to be aware of it right?
For a sense of scale, I googled "raises $15000 for breast cancer" and found the following folks who had also raised $15000 for breast cancer sans worldwide brouhaha:
"Maquette Bank Employees Raise $15000 to Fight Breast Cancer"
"Buckley Senior Raises $15000 for Cancer Research through Cabaret"
"In conjunction with Breast Cancer Awareness Month, Special Effects Hair Salon raised over $15000 hosting a Cut-A-Thon fundraising event..."
However for something so revolutionary, it takes more than just being a slacktivist who sits their ass on a comfy chair while doing a 'political reformation'.