For business desktop environments I recommend Novell SUSE Enterprise Linux for medium to large enterprises and openSUSE Linux for SME. Businesses that want to operate their own web/email/application/database servers, I recommend Red Hat Linux and Feodora Linux.
Red Hat, Fedora, Novell SUSE and openSUSE Linux has an excellent record for security as they come bundled with the SELinux (Security Enhanced) kernel developed by the US National Security Agency (NSA). The SELinux kernel prevents unauthorized users, applications and processes from making changes to system settings, processes, data or install applications. Only authorized users may change specific data, settings and control specific processes. All processes operate in a sandbox and are only allowed to perform specific tasks. Only the administrator can perform application installation, change system settings, configure processes etc. In other words the administrator is the only user that has total control of the system. Also, all users MUST be password protected. The cause of the most security issues on Windows is no user, including the administrator, requires a password. The vast majority of Windows users, including IT staff do not know to password protect the administrator user account or to set the non administrator user accounts to standard user. By simply password protecting the administrator account and setting all other users to standard user will prevent most malware from being installed. If a virus is prevented from being installed it cannot infect the system. The same for spyware, Trojans and all forms of malware that attacks the operating system.
The reason Linux use is discouraged by the IT security industry is because of it's legendary security effectiveness. If Linux was used as widely as Windows in the business community as a desktop and server environment, there will not be as big a demand for security products as there is today. Why spend thousands of dollars per year to secure a system when it is already secure? The reality is spending thousands of dollars to secure a Windows system will only limit the exposure to threats but do not provide the protection that Linux provides. There are very few security firms that provide security products for Linux, especially x64 Linux, as they are not required except for very specific situations like securing the web/application/database/email servers of human rights organizations, financial institutions and certain government departments like defense, commerce, foreign affairs and treasury.
If the company referenced in the article was using x64 openSUSE Linux (free to use, no licensing fee), they would not have been affected as 64 bit chips has a special security system hardwired into it that prevents malware from running. If the company was using standard (32 bit) Linux, the malware would have run in memory therefore compromising the computer for the duration the user was logged in. Once the user logs out, the malware would be flushed from memory but the attacker would already have accomplished their mission. This is also true for standard Windows (all versions of 32 bit Windows) whether there are security software installed or other security precautions are taken or not.