http://www.scmagazineus.com/Trojan-targets-Mac-users/article/58290/
Well, well, well - A professionally crafted - in the wild - trojan that targets Macs. This is not a proof-of-concept, but existing malware. Here's a quotable quote from Sunbelt Software's President, Alex Eckelberry:
The Mac is emerging as a more widespread platform in general. I think Mac users need to get off their complacency about Macs being safe.
How long until Linux gets hit? The more market share it gains, the more likely it will happen. That's when we will find out what weaknesses may exist in Linux that have gone heretofore unknown due to the "obscurity" factor. Can it stand the onslaught of organized crime targeting Linux users? Time will tell!