You can clone with
HTTPS or Subversion.
The IRC bot should also notify about Wiki change events.
/cc @technoweenie - I'd like to understand the plan for adding other types of events like these too.
The IRC bot only responds to push/issues/pull_request events. A Wiki handler can definitely be added. Unfortunately, there's no way to configure this in the GitHub hooks UI. There's just no spot to set what events a hook should listen for. You have to go through the API currently.
Some hooks have a default set of events though.
@rtomayko: I'm definitely campaigning for someone to give the Hooks UI a refresh :)