This list is maintained by Thoroquel Systems LLC from Columbus, Ohio. The list has been initially created for their personal use but now is in public beta. They do not recommend using it directly to block connections.
XPEWS is a *PEWS style list. Therefore you should expect whole blocks to be listed.
Delisting is possible if you meet their critaria. The list of things to be carefull during requests is listed on their website.
Is the information on our site wrong or incomplete? You don't want us to monitor your blacklist? Or do you operate a similar blacklist? We would like to hear from you!