You couldn't have missed that Apple just released Snow Leopard, the latest version of its Mac OS X operating system.

In Apple's own words, it has "refined, not reinvented" the operating system, and is focusing firmly on the future. So it's out with the old guard of Power PCs and welcome to a new 64-bit, Intel-only operating system.

The operating system software certainly seems to have had quite a speed boost, with claims that many core operations are faster by at least 40%, and some programs (such as Finder and Time Machine) twice as fast as before.

Snow Leopard's security improvements include Library randomization, Execute Disable (to protect Mac memory from attack), sandboxing, and anti-phishing features in Safari, but the most interesting thing to us is something that Apple didn't reveal in advance: protection against malware.

Although some are portraying this as Apple building antivirus into its new operating system, that's not quite true. The new anti-malware functionality in Snow Leopard is not comparable to the protection that existing antivirus solutions offer.

Snow Leopard doesn't offer on-access scanning for malware (which can, for instance, stop you from copying an infected file from a CD ROM or USB stick) or clean-up. Instead, it only protects against two families of Mac Trojans, and even then only when they are downloaded from the Internet using Entourage, iChat, Safari, or a handful of other applications.

That means, for instance, that if you download Mac malware via BitTorrent, Snow Leopard won't be any defense.

But this is Apple's very first step in building anti-malware functionality into its products, so given how many Mac users have their heads in the sand regarding computer security, this has to be a good thing.

My hope is that over time Apple will strengthen its anti-malware protection and better defend its users from all of the possible vectors of attack. And I hope the company has the vision to work closely with the security industry (like Microsoft does with the MAPP initiative, for instance) for the benefit of all computer users.

Yesterday, many thought it was uncool to run antivirus on their Apple Macintosh. Now no one can seriously hold that position.

Graham Cluley is senior technology consultant at Sophos, and has been working in the computer security field since the early 1990s. When he's not updating his other blog on the Sophos website, you can find him on Twitter at @gcluley. Special to Dark Reading.