Vitalik Buterin (@vitalik.eth): [Farcast] @cassie The difference is in the edit capabilities:
Estimated coin impact
Scores are not price-change percentages. High impact means a score of +70 or more, or -70 or less.
Impact unavailable
[Farcast] @cassie The difference is in the edit capabilities: Easy: append-only Medium: linear list, edit your own value in place Hard: key/value store, each user needs ability to create new values in arbitrary positions