Assumption:
There is a market for censorware.
I wouldn't buy it so I don't look for it, but someone is making cash from it.

From what I have read the problem is that it is uniformly and deliberately obscure in how it operates at a technical level.

Write (or maintain and support a GPL/BSD/etc , hell even closed source if you can withstand the wrath of RMS) an extensible tweakable censorware product. For schools, libraries, corporations, small business, even for the fundies (especially them as they have cash - sell the licences based on the size of their congregation).

As the blocking parameters, rules and algorithms could be tweaked to suit the client (through a user defined and Seth supported list format), everybody would get what they want.

Then you can rag on the others (or have the hacks do it for you) through the trade magazines/blogs for being backward, obsolete, not Web2.0. The only way to defend themselves is open up. Or they can sue. But that is what the money is for.

Be the problem, not the solution. Until you get bought out.

Sigh. You've re-invented Open Source Censorware.

1) There are already people doing it - the fact that you haven't heard of them shows how successful it is.

2) Censorware is bought mostly on marketing, not quality.

3) Censorware is inherently user-hostile, and therefore evil.