The biggest benefit of open sourcing DDG in your case is that it would be useful as research to programmers who are developing something similar (e.g. a search

The biggest benefit of open sourcing DDG in your case is that it would be useful as research to programmers who are developing something similar (e.g. a search engine, wikipedia parsing, crawlers). You might also think of extracting some common functionality into a project which could be directly used by programmers. That would also give you the chance to form a community. Examples: Tornado web server (Friendfeed), Cassandra (Facebook), RoR (37signals).