This is just a weakness of the original formulation of the Turing Test - for a machine to fool a human into believing that it is, in fact, a human. But we don't really need that, do we? What we need is for an AI to "fool" us into believing it is truly intelligent. For that, I don't care if it knows all the capitals or can do complex maths. In fact I expect it to be able to do that. I already know it's a machine, after all.

Unfortunately that is far more subjective test. It's easy to devise an experiment based on the classic Turing Test, you just put some people in a room with some terminals, some of which are wired to computers and some of which are wired to humans, and have at it. But it doesn't tell you much, really. But whether a machine that can convince you it is intelligent, is in fact intelligent, is not really a scientific question, and as such doesn't really have a scientific (that is to say, satisfying) answer.

What I'm getting at with this is that the important question to ask about AI is the same question you can ask about other humans, and the answer for either is the same. The difference is that solipsism is a lot easier when you're talking about machines.