And with that came a rarely seen acknowledgment from Apple regarding security.
"Innocent-looking files downloaded over the internet may contain malicious applications, or malware, in disguise," a page on Apple's website said. "The Mac is designed with built-in technologies that provide protection against malicious software and security threats right out of the box...However, since no system can be 100 percent immune from every threat, anti-virus software may offer additional protection."
The page also lists a number of Mac OS X security features, such as sandboxing, which helps prevent what a malicious program can do on a user's PC, and Execute Disable, which can safeguard memory if an attack occurs.
This appears to be Apple's first public reference to security since December, when it published -- and then subsequently removed -- a support document encouraging Mac OS X users to use anti-virus software.
Mac security solutions provider Intego said in a memo Wednesday that the more information that Apple publishes on security, the more informed customers will be.
"Apple has finally recognized what Intego has been saying for years: that Macs are not immune to viruses and malware," Intego CEO Laurent Marteau said.
The Cupertino, Calif.-based computing giant often bears criticism from the security industry over what they perceive to be brash claims concerning the security of Mac OS X versus Windows. Others have questioned how effectively Apple responds to vulnerabilities.
In a blog post last week, security analyst Rich Mogull of Securosis listed five suggestions for Apple.
They included appointing a chief security officer, adopting a secure software development program and creating a security response team.
An Apple spokeswoman did not return a call for comment.
Meanwhile, earlier this week, security firm ParetoLogic disclosed a new Mac malware variant disguised as porn.