BBC News, Monday, 14 January 2008:
Owners of Blu-ray DVD players may find themselves frozen out of future developments in the technology because their machines are not upgradeable.
The Blu-ray camp has recently rolled out new features for players, which include picture in picture options.
But the majority of Blu-ray players sold to date do not have the necessary hardware to offer the features.
Some discs already come with a note telling users that they may need to upgrade software in their machine.
In some discs, the note reads: "To ensure the best possible viewing experience, your Blu-ray disc player may need a firmware or software update."
But these updates relate to improvements in playback and do not offer a pathway to the new features.