Ease of Use — the editor experience should not be intimidating and should facilitate quickly getting straight into the code
Real-time Collaboration — sharing live coding sessions with colleagues should be easy and collaboratively coding with one or more partners should Just Work
Integrated Command-Line — tools like vi and Emacs have demonstrated the power of integrating command-lines into editors; Bespin needs one, too
Extensible and Self-Hosted — the interface and capabilities of Bespin should be highly extensible and easily accessible to users through <a href="http://labs.mozilla.com/project/ubiquity/"target=_blank">Ubiquity-like commands or via the plug-in API
Wicked Fast — the editor is just a toy unless it stays smooth and responsive editing files of very large sizes
Accessible from Anywhere — the code editor should work from anywhere, and from any device, using any modern standards-compliant browser