So unless you run the Adobe Updater immediately after install (Which seems to have issues with UAC unless you explicitly launch Reader as an Administrator), or make the effort to find the patch to 9.3.1, your machine is going to be at risk every time you open a PDF and most people will have no idea they're running unpatched.
Spad writes: "Zeropaid is reporting that as part of its ongoing lawsuit, the RIAA will be seeking the maximum $150,000 per song for each of the 11 million MP3s downloaded from the Russian AllofMP3.com between June and October last year. This amounts to $1.65 trillion, probably a tad more than AllofMP3 has made in its lifetime. A representative of AllofMP3 stated: "AllofMP3 understands that several U.S. record label companies filed a lawsuit against Media Services in New York. This suit is unjustified as AllofMP3 does not operate in New York. Certainly the labels are free to file any suit they wish, despite knowing full well that AllofMP3 operates legally in Russia. In the mean time, AllofMP3 plans to continue to operate legally and comply with all Russian laws.""