The poster you are responding did not claim that humans are the shit. They merely pointed out the fact that we have so far proven incapable of proving that we aren`t said shit. Now, you could argue that such a hypothesis could only be falsified by the construction of a machine consciousness. That, however, is orthogonal to the fact that it remains possible that there is in fact some bizarre quality of the universe or the human race that makes machine consciousness impossible. Not a terribly scientific position to take, perhaps, but a perfectly sound philosophical one.
No, human intelligence is an emergent quality, and I fathom that even our massive representations of humanity's information (akin to what Google is compiling) will soon begin to exhibit interesting qualities of its own once it becomes complex enough to exhibit perhaps interesting, unanticipated emergent qualities (in fact, if it didn't I would be absolutely shocked). Many strange and unpredictable (or at the very least unanticipated) things arise from even the simplest of "complex systems" (Conway's game of life and some of Wolfram's automata), much less the wonderful systems detailed by our individual neural mappings and our individual genomes. (q.v. http://en.wikipedia.org/wiki/Emergent_behavior)
People always think that some human will "write" an AI like HAL or the like, but it is much more likely that nature will roll its own AI once we have made a comfy enough nest for it to germinate. After all, isn't that how we got here? (from an evolutionary biologists standpoint anyhow...)
And again, sorry for being contentious. I just despise the "religious" argument (even if there is no "named religion" being expounded... Let's keep Ockham's Razor at the ready here....)
From the biological point of view, the simplest species is AS SUCCESSFUL as the most complex species, since both are still alive and procreating.
Why do humans have eternal significance? To whom?
Known to who? I don't like this very self-referencing way of thinking. Very similar to the discovery of America... people were already in America way before Columbus came and "discovered" it. (although apparently he didn't even realize he hadn't arrived to India)
He/She's allowed to have such an opinion, but this discussion is trying for a particular feel and that isn't contributing helpfully to it.