It should also be mandatory for bhw to babysit my children and make my morning coffee for me.
I'm not trying to flame you, just taking your comment to the absurd. Exploits with PDF's, image files, and a number of other file extensions that used to be considered of no risk as disease vectors have been around for quite some time. Hell, a few weeks ago someone figured out how to make windoze shortcut files (.lnk) malicious.
I independently scan *everything* I download - not just what I download from bhw, but anything I get from the web. WizGizmo put up an excellent sticky after the recent spinnerchief clusterf, and we all know that VT scan reports can be spoofed...we each need to take some responsibility for what we download (that was partially the gist of Wiz' sticky).
There are other methods for securing your computer that have been discussed - different mixes of hardening software and hardware, *nix, virtual machines, and so forth. All depends on how deep down the rabbit hole you want to go.
Again, not a sermon or a flame, just a thought.
peace - gregs.