Mac users can't afford to be cocky about security

Ron, on our list, has regularly posted good advice from the security people at Sophos. In fact, it wouldn't be a bad idea for subscribers of this BoiseMacs Maclog to also follow Sophos' Graham Cluley's blog. Or follow him on Twitter @gcluley. In any case, this recent post (which includes a choose-to-play YouTube video to illustrate) demonstrates how a widely-followed and (one would think) reliable person like Guy Kawasaki (who actually has ghost Twitterers, but I digress) was used as a dupe to point people to an infected site that had (equal opportunity!) downloadable and installable Trojan for both Mac or Windows users. Since Mac users can't afford to be laissez-faire any longer about malware protection, and since the estimable Sophos just provides software for enterprise or small business set ups (smallest package is for 5 Macs), what is the best course of action?