When account is created in site, the account will be created in other sites..
When user profile is updated in site, the changes made will reflect in other sites..
You can choose which of the user activities should be shared to your Remote Sites..
Upload the plugin files to the wp-content plugins share-logins directory, or install the plugin through WordPress plugins screen directly..
Activate the plugin through the Plugins screen WordPress.
Use Share Logins screen to configure the plugin..
That means, if user logs in to site and his username is johndoe, it'll look for the in other site and if found, the user will be logged in...
If the username isn't found in other site, the login to other sites won't work.
But, please keep it in mind, the more sites, the more laodtime...
Interested in development.., check out SVN repository, or subscribe to the development log by RSS...
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