what is corrupt is when editors ensure their own sites have multiple listings and their rivals are booted out of the directory
This is almost becoming a cliché. If there is so much corruption happening, why are people not reporting it? There is a very good system for reporting abuse in the ODP (search on "dmoz report abuse") and yet we see very few reports with verifiable evidence. Just because your web site hasn't been listed it doesn't mean that there is some type of abuse happening.
That's not to say that there aren't editors with their own personal agendas, but for the most part those people are usually dealt with pretty swiftly - and if you really do have evidence that someone is abusing their privileges, please do report it. We can't fix it if we don't know about it.