Is it even necessary?
First of all, QT is not only pointless (as a player) it is also a bloat, although available freely. Updates are released occasionally, as and when required. As for running on OS X, I believe, though correct me if I'm wrong, it is included with the OS and therefore (like M$ Internet Explorer) subject to attacks from hackers because of the wide user base. Therefore, updates are 'probably' a good thing! ;)
My advice to people using QT on Windows is download the Quicktime Alternative (also free but 5-16mb lighter) as it does not create all the registry keys, startup items and system tray tasks the "official version" does. Admittedly it is a third party hack. It is open source though I believe (although I won't eat my hat) and if so is open to public scrutiny and/or reprogramming.
Comments welcome, criticism more so.
Hey if I'm wrong, tell me, if I'm not however, well, just bask in my sunlight :)