The SEs really aren't as stupid as you assume. They aren't going to be moved, one way or another, by PR efforts in ANY medium. They already know about the ODP--not as a PR project but as an information source. They don't care how many people use it directly.
They'll make their algorithmic decisions based on whether their (extremely bright) techies can figure out a way to use ODP data to improve their search results.
But, in any case, SE use of the ODP to improve searches falls into the category of "clever abuse." It is neither contemplated nor forbidden by the ODP License. (There's a reason it's not called the Open Search Engine Seed Project.) But we're just building a directory. The decisions we make are based on which action builds a better directory. The point is to build a directory.
There are many people working on other media. There's no reason to deprecate their efforts. But there's no reason to compete with them either. For one thing, some of them (Google) undoubtedly do their own thing much better than we could. For another thing (as has often been pointed out) the directory would profit by many improvements, and efforts in other media would dilute the effort given. For another, there's no reason to suppose that a community formed to build a directory would necessarily be well equipped to work in another medium, nor is there any reason to suppose that people who can't contribute effectively to a directory should be excluded from work in another medium. For yet another, there's no reason to suppose that the organizational structure and processes designed around building a directory would be efficient for other media -- certainly Project Gutenberg and Wikipedia, for instance have distinctly different structures although sharing many of the same ideals. Finally, individual volunteers are able to participate in multiple volunteer projects, depending on the breadth of their own personal goals -- so there would be absolutely no point in any one project trying to be everything to everybody. Focus is good.
But variety is good also. It is better to light a candle than to curse the people who are lighting candles somewhere else. If you see a need that the ODP doesn't fulfill -- and there are many of them -- join a project that's working on that. Or form a project: start doing the work yourself, and invite people who share your goals to help.
