QuickTime X is only required for the desktop, but Safari can play HTTP Live streams natively within the <VIDEO> element. Have a look for yourself [test URI]: http://devimages.apple.com/iphone/samples/bipbopall.htmlHTTP Live Streaming does need Quicktime X, get over it.
Note: The samples [see links below] show the same NTSC test pattern at four different resolutions and data rates. The last sample streams at multiple data rates. The stream starts with sample 1 and switches to the fastest sample the connection supports.:
http://devimages.apple.com/iphone/samples/bipbopgear1.html
http://devimages.apple.com/iphone/samples/bipbopgear2.html
http://devimages.apple.com/iphone/samples/bipbopgear3.html
http://devimages.apple.com/iphone/samples/bipbopgear4.html
Edit: I'm pretty confident that embedding the video stream URL in a HTML page will work with other browsers, simply because the StreamingMediaGuide.pdf [on page 20] reads: "To view the sample streams in browsers other than Safari, the QuickTime plug-in or ActiveX component is required."