Just a day ago, I noticed ‘sysadmin’ user in SQL Server 2008. While looking more into it, I found that it has same account rights as ‘sa’ account. ‘sysadmin’ is actually replacement for legacy ‘sa’ account. ‘sa’ still exist in SQL Server 2008, however, it will be deprecated in future versions of SQL Server. It is recommended to all the users who switch to SQL Server 2008 to start migrating to ‘sysadmin’ from ‘sa’.
Additionally, security is improved in SQL Server 2008 from SQL Server 2005. In previous version of ‘sa’ account were allowed to create without password, however in new version of 2008 ‘sa’ account can not be created without providing password.
Summary, start migrating from ‘sa’ to ‘sysadmin’ as we upgrade to SQL Server 2008.
Reference : Pinal Dave (https://blog.sqlauthority.com)