WHY DID SIGGI DELETE ALL THE PLOTS
Siggi didnt delete all the plots, try checking out /server CreativeOld or click on the [join] button on glist for old creative. I believe they are trying to migrate all the creative plots on the old server to the new one so that people wont get stuck in corrupted chunks anymore. For further information on migrating plots, check out the old creative spawn. there will be instructions there.
-Noob