Apple states the component is unnecessary in Lion onwards, however MPEG Streamclip still needs it.
The installer of the MPEG-2 Playback Component may refuse to install the component in Lion. The QuickTime MPEG-2 Playback Component is not required and cannot be installed. On OS X Lion and later, MPEG-2 playback functionality is built into QuickTime X. This particular aspect is a bit complicated!Īs you can read on this page: or-mac-os-x