Sites can easily adapt their services to the needs and desires of their users.
They
can do it today using site specific settings. I am pretty sure that these
settings
require more than just one bit, ...
Here's a concrete suggestion: the Bing search engine and IE browser
support this safe flag right now. Could you talk to the people
responsible for them and ask whether they considered more fine grained
schemes such as PICS, and why they implemented a single bit instead?
R's,
John