Proof of concepts are out there but end users have not been affected by exploits in the wild the way they typically are with some other platforms. It's never good to say don't be concerned about security, however, the actual effects on users of our platform are minimal.
We're in the process of investigating and addressing them. I think it is important to note that although these are potential vulnerabilities, there are no know exploits to them and they are not affecting customers today.
There is certainly a tendency to make news out of every potential exploit on the Mac simply because it is more unusual than on some other platforms. A lot of times when you look behind the news, it is a little bit of a stretch.