I am sad to report that this site was hacked on March 8th and was not noticed until March 11th.  I had gotten a few reports from people that their AV was blocking access to the site.  After investigating, I noticed that files were uploaded to the site which place a malicious piece of javascript to the top of each page.  I'm not sure what the javascript's payload was since my systems are fully updated, nor was I able to establish the attack vector the hacker used.   However, i've cleaned the infection and tightened security on the site by a fair bit. 

I'm sorry for any trouble this has caused for anyone.  I guess once something becomes popular enough, it's ripe game for the hackers.  *sigh*

Mike