Also vital to me is easy copy/paste insertion into a note of clickable links to a file on my system or a URL, to which I can add my annotation about the file or webpage etc.
My final essential requirement is keyboard shortcuts as I hate being slowed down by having to move my hand continually between keyboard and mouse. (Gmail is superb in this regard.) I feel such shortcuts provide flexibility, which is desirable (everyone works differently; a good program should cater for all the main ways: in this context mouse, keyboard, tablet). Also, keyboard shortcuts are of course a very good thing for reasons of accessibility for people who can't use a mouse - accessibility being now a hot topic, and in some countries essential for legality.
I have Microsoft's OneNote, but found that, for the way I work, it's cumbersome and unintuitive to use.
After some research I've settled on three possible options, and I'll be trying them all out over the next month or so and reporting on the results:
- Evernote, currently downloadable as a free beta and using a "endless tape" system
- Zoot, an "information processor" which is available on a free trial and
- General Knowledge Base from Baltsoft, shareware which seems to have Outlook-type categories and a full Word-like editor for individual notes.