After create a new account, there is the Atlassian Events and other marketing relates notification were checked the box by default in the Atlassian | Email and Privacy Preferences page : http://my.atlassian.com/email

It would be great if there is option to disable the notifications by default when create new Atlassian account.

Workaround

It can be verify or update their own settings by logging into their Atlassian accounts and visiting http://my.atlassian.com/email