My Mac Mini has been in service since Nov 09 without any AV program. With all the discussions of to run or not to run AV, I decided to download ClamXav and scan my computer.

Program downloaded, entire computer scanned. Nothing found.

I also did the check for Flashback prior to the Apple fix, and found nothing there either. I have disabled Java. I did apply the Apple fix.

At this point, I don't think I need to worry about viruses, or malware, but I will maintain vigilance and perhaps scan weekly or monthly.

Thanks to all the forum experts who have offered opinions.