In client-side scripts, this method will return a transaction id for the async request that can be used to cancel the request. In server-side scripts, this method will return the JSON response object (first parameter of the success or failure callbacks.)
Creates a new user account. To create more than one account, provide a semicolon separated list of email addresses. If all of the provided email addresses are valid, new accounts will be created for any email addresses that are not already registered users. Already existing accounts will still result in a call to the success handler with a message indicating that the user account already exists. If multiple accounts are being created and one or more result in an error but there was at least on successful account creation, the success handler will be called with the "users" information along with an array of "htmlErrors".