I can see Google Docs & Spreadsheets being used by the Board, the Friends, TAC, LAB, and other formal or ad hoc library groups. This would allow input from many individuals who might not be able to meet face to face as often as needed.
Since you can edit with your partners in real time, the endeavor is truly collaborative, rather than becoming a free-for-all. You can also see who changed what, and when.
As far as general library patrons using these tools, we could put an explanation on our web site with a link to Google Docs & Spreadsheets. High school students who often collaborate on assignments might find these tools to be useful, and could access files from home, school, or the library.