Stopping griefers cannot, and should not, the top priority. If it was, then everyone should not be able to build or destroy, because that will stop all griefers. You should also remove chat, because people can grief with it. This is obviously not a good idea.
The top priority is to make a fun game for everyone. Anti-griefing measures should not hinder this. Done properly, they might be a vital part of it, but making a fun game comes first. Becoming absolutely paranoid about griefers will strangle the game.
Its almost like they forgot what game they are playing.
This is sandbox people. Think of it like the beach! Your the wimpy kid with the sand castle, in a public place, some bully can totaly destroy your sand castle. Mean, yes. But its probably going to be part of this game big time. You build your castle, in the end someone will find a way to destroy it.
Is destroying stuff cheap right now? Yes, BUT, there is hope for the future.
The "Greifing", will probably simper down and turn more creative when monsters and pvp come into play. Either way, shits going to get destroyed.Folks are going to have to accept that fact.
You see those cool cannons throwing tnt everywhere?! People aren't just going to use that for mining.
Sirs, this topic is over 9000 10 months old. In the course of this time, custom server software with zones/teleport/multiworld/who broke or made a block have been made. See McZall (now MCLawl) for example.