QuickTime Media Format
With Apple behind this video format it was always expected to be a leader due to all of the users that consider Mac the leader for video editing and production. As far as streaming media goes this format never really got off the ground. Most of the content that you have seen as Quicktime was probably progressive download and not actually streaming. While it is a fine format for local viewing or for progressive download type content, the quality and performance of the streaming platform has never been on par with the competition.
For live streaming the only broadcasting software that Apple released was for Mac only which made the market for the product fairly small. There are very few hosts that ever offered live streaming of Quicktime video.
For many years Quicktime was used to supplement one of the other formats for Mac users but with the newer crossplatform formats of Flash and with Microsoft’s Silverlight platform the need for a Quicktime version has virtually gone away.