I try with Firefox 11 nightly 32bit and IE 9 32bit on this page http://www.tvonline69.net/ with the last vlc win32 nightly build, on Firefox vlc crash and on IE 9 nothing happens.Try win32 nightly build from the same date to rule out a win64-specific bug.
It is listed, but it doesn't work. Installing as admin change nothing.It works for me but only because I had copied the npvlc.dll to program\ files/nightly/plugins/ directory manually.
Perhaps there's another key for win64 version?