When a story like this is posted I wish they would give some additional information.
Visitors were getting redirected to an exploit kit. For practical countermeasures (on Windows, anyway), I can especially recommend steps #3-#9, plus #16, in my Windows security guide yonder:
http://www.mechbgon.com/security
These exploit kits will survey what you've got to attack (your browser, plug-ins, utilities, media players and OS), then take their best shot.
Java's the top target; if you don't need it at all, uninstall it completely. If you need it for something other than Web browsing, update it to the latest version and disable it in your Web browsers completely:
http://krebsonsecurity.com/how-to-unplug-java-from-the-browser/
Adobe Reader is another target. Uninstall older versions (8, 9, 10) and install Reader 11 (Adobe's FTP site:
ftp://ftp.adobe.com/pub/adobe/reader ), then lock it down by going to its Edit > Preferences and doing like this:
There's more you can do if you want:
http://security.thejoshmeister.com/2010/05/7-easy-steps-to-increase-adobe-reader.html Alternatively, if you're on Windows 8 (yes, all three of you), then you can use the built-in Win8 PDF reader.