Current Position:Home > State of Mac security?

State of Mac security?

Update:10-11Source: network consolidation
So, I keep getting these emails from Comcast's Constant Guard service claiming "Constant Guard from XFINITY identified that one or more of your computers may be infected with a bot."  They seem to be dead serious about it, though Comcast never provides any details about what triggered the email. They only provide a link for you download a free copy of...ew...Norton.
But, the security emails keep coming, about once every two weeks or so. Something is triggering Comcast's snoops to raise a flag my way. I think it's just occasional spikes in traffic due to suddenly having three computers online, but it's not something I can prove.
Has anyone else been the recipient of these Comcast emails? I also tend to be of the opinion that the Comcast emails are largely a marketing campaign, since they also direct you to their own for-fee security service.
So, what's the state of Mac security today? Are there really any bots that can make a home on a Mac these days?
FWIW, my home network is an iMac, two iBooks and, occasionally, an iPhone, connected via an Airport Extreme Base Station (WPA2).

The Best Answer

Technically your Mac can become part of a botnet if you installed something unawares of what it was.
There has been a Mac botnet back in 2009. net-is-active.ars
You can check with this site to see if your IP address has seen traffic associated with a botnet.
Could be those emails are phishing scams. Visit their site and see if there is any official word about these emails.
Comcasts DNS servers get hacked from time to time.
Use OpenDNS or Google DNS instead, only take second to reconfigure the router.
Norton is the last thing you want on your Mac, ClamXav would be the only good solution I would think.
Of course simply reinstalling OS X  on top of the installed version and then Software Updating should clear out anything in OS X, but then third party programs and plug-ins should all be reinstalled.