Use flash, both the methods stated require the user to have software installe. Quicktime is the better choice, more common, though it is very slow to load on general computers. It even used to freeze browsers on my parents computer (2ghz P4 thingy). Flash is essential for web browsing these days.
http://www.rawr-designs.com/tog/ hit the Preview RAWR-Player. Thats a VBR 133kbps .mp3 file supplied for use by rejetto himself
btw, don't consider as download will just make the counters ignore it. Mav has the idea with the open in browser option in HFS