As we are in election period, I don't get the difference between getting to 10k reputation point and the diamond. What additional controls do you earn with the diamond ?
It is all documented here.
And 10k is documented here in greater detail. Jeff's link is more for diamondy goodness.
Moderators have the same privileges a 20k user has; the following then applies for moderators:
- On voting, the action is taken immediately. This is true for voting to close a question, or deleting a post.
- When a post is deleted by a moderator, users cannot vote to undelete it; it is necessary for a moderator to undelete it.
- The flags a moderator can cast are unlimited.
- Moderators have access to additional tools to convert posts, such as making a question and its answers Community Wiki, or set a post as not CW; in the latter case, a post will never become a CW. Moderators can convert an answer into a comment, or an edit for the question, if the answer has been given from the OP.
- Moderators can merge tags, or create synonyms independently from the score they have for the tags they are handling.
- Moderators are the only ones who see comment flags, even though they don't see who cast the flag.
- Moderators see all types of flags, while other users don't see flags for which a custom reason is entered.
- Moderators can contact a user, or suspend users.
- Moderators see the past names used by a user.
10k Reputation allows you to vote to delete and undelete content on the sites you have 10k rep on. It takes 3 10k user votes to delete or undelete content. A moderator (ones with the diamond) can close and reopen at will with a single click, as well as delete and undelete with a single click.
Moderators also have the ability to lock posts, merge posts, convert entire threads or single answers to community wiki. There are numerous moderator tools to aid in finding vote and user fraud and dealing with unruly users (suspend, delete, destroy).
Both 10k users and moderators can see items that have been flagged as Spam or Offensive. Only moderators can see the items that were flagged for moderator attention.