It's really a terrible news that Google stopped the development of notebook. Recently I have decided to make good use of notebook and cleaned up and cataloged the web clips in it, then the news comes.
I think notebook is really a helpful tool to orgnize information, and don't know what reason made Google stop it when no better alternate product comes out. Maybe some day, Google says Gmail is out of service...
Hope Google don't go far that way. It is all the faithful users that make Google so successful and dominate web world.