Worst move by far is putting out ebooks that haven't been proofread. People here tend to be a bit jaded by it by now, but it's a big shock to newcomers who are more used to real books.
Best, probably all the new writers who are able to reach an audience that we would have otherwise never had, writing about subjects the traditional publishers aren't interested in. Though that could also be a bad thing as well when they rush into it
