This looks less like something specific to the iPhone and more like Apple finally fixing an embarrassing issue with QuickTime. QT tried to support streaming media in the same manner as RealMedia and NetShow (now part of Windows Media), but it never got the same degree of performance as the other two. (Which is really a condemnation, since their competitors haven't done a real good job either! It left Adobe/Macromedia a wide opening for Flash to get through!) Apple used to use QT streaming as a showcase for showing Stevenotes and other live events as well as demonstrating their once commitment to open source by making versions of the streaming server available for other OS platforms.
It may be making purses out of sow's ears at this point... As impressive as QT once was, it really is a creature of the CD-ROM multimedia era, and it really shows if you've ever worked with the APIs like I have. (There were design considerations for driving laser disc players via HyperCard in it's original specs!)