When I was using Maxthon, there used to be a good plugin for noting down and aggregation of information. It was not a great implementation but one I used very often. Ofcourse GDS sidebar offers a scratch pad that I use now for quickly noting down information. But it is another story if it is an organized application.
The recent releases of Google included GDS 4, Google Co-Op and trends. Google will hopefully release the notebook this week. ZDNet reports about it and links to this flickr page that contains preview images of the same. Really, cool app, as usual. Waiting to lay my hands on it!