While searching for Google Notebook keypad shortcuts, I found by chance a published notebook (from Ionut!), which gathers Google apps shortcuts:
http://www.google.com/notebook/public/10082229128833698422/BDQFPQwoQ35SekYwi

I love shortcuts since it saves me 10% of my working time. But there's no help for Notebook, which becomes a central app when web-working.
I only know how to open the Firefox extension (Alt + N) but I would like to be able to
1) bookmark a page directly
2) to close the extension.
3) plus any other trick.

Any idea?
PS: As Google will probably release a new Google Toolbar for FF3, I think this thread will soon lose its (potential) interest...

Ok... 'escape' was an obvious shortcut to close the extension. So obvious that I missed it :S