[piramida]

The reason they failed is fairly simple. People are not that smart, on average, so the usage of their service, besides initial "have some fun" period, is limited to data researchers (of all kinds), scientists and students.

It may be not the smallest audience, but I think their best bet would be working on direct deals with schools and universities instead of trying to attract small-scale developers -- why would developers be interested in a project that probably won't ever pay back but will start charging after 2000 uses?