A general purpose dialog system and a domain specific question answering system are two different things. It’s true that most basic knowledgebases at least begin with FAQs, or wikis – think question-answer pairs. Most dialog systems, and question answering systems, are just a sophisticated form of search. The one thing that the Turing tests have proven is that human dialog is more or less mind games, smoke and mirrors; in other words, it’s not difficult to fool people into thinking something is intelligent. In order to beat the, really a lot of effort is required to build the knowledgebase, in which case you may as well go ahead and write a book on the subject – think PhD. Or, as my nieces pointed out, nobody wants to talk with a bad robot….