A perfect storm of backlash against Facebook's privacy issues combined with major media coverage thrust them into the spotlight - their original ambitions for the project and fundraising goal of $10,000 were set before that happened. By no means do I see that as "over-promising in order to get money."
Even asking for $10,000 was major hubris that made me skeptical they were up to the task. But they could have been more honest about their capabilities, timeline, roadmap, etc. in order to put things into perspective and bring the hype down a notch. They most definitely over-promised, even if they had only received the original $10k