Share Google Spreadsheets & Docs with "Users"

Currently, Google Spreadsheets and Docs allow you to share your document with either a Viewer, who can not modify it, or a collaborator, who has full editing access.

On the day after Google Spreadsheet launched, I proposed to create a third type of sharing - with a "User", only allowing the modification of cells specifically identified as "modifiable by users." This would allow a complicated spreadsheet to be posted for everyone's use without anyone being able to edit the formulas by mistake.

When applied to [Writely] Google Docs, it would allow the author to post forms, and then possibly collect response data via GoogleBase which should be auto-setup when the author posts a form.

Original post is here; The countdown to implementation has started...