How's about this: The AGI is a multi node peer to peer system, implementing a general behaviour protocol on each node that allows cognitive cooperation of the nodes, just as the mankind does (the AI is more similar to mankind than to a man due to the computational structure of 'fast nodes, low bandwidth links'). Due to simplicity of implementation of individual nodes, the humans are treated as a form of intelligent nodes (even if slow), and the rules created to prevent a range of forms of non-cooperation between nodes (ranging from elaborate modelling of each other, to loss of information, to outright warfare), ensure mutually beneficial integration.
Meanwhile, the simplistic and philosophical reasoning on the subject with no respect for subtleties of implementation proves entirely irrelevant, as is virtually always the case with simplistic reasoning about the future.
edit: what ever, get back to your simplistic and philosophical reasoning on the subject, it pays the bills, it gets donations rolling, it is easy, while the actual reasoning about how AI has to be build just explodes into enormous solution space which is the reason we didn't yet build an AI.
This isn't responsive to Kaj's question. In this scenario, the AGI systems don't need humans (you're not describing a loss in the event of humans going extinct), they preserve them as a side effect of other processes.
As Luke mentioned, I am in the process of writing "Responses to Catastrophic AGI Risk": A journal-bound summary of the AI risk problem, and a taxonomy of the societal proposals (e.g. denial of the risk, no action, legal and economic controls, differential technological development) and AI design proposals (e.g. AI confinement, chaining, Oracle AI, FAI) that have been made.
One of the categories is "They Will Need Us" - claims that AI is no big risk, because AI will always have a need of something that humans have, and that they will therefore preserve us. Currently this section is pretty empty:
But I'm certain that I've heard this claim made more often than in just those two sources. Does anyone remember having seen such arguments somewhere else? While "academically reputable" sources (papers, books) are preferred, blog posts and websites are fine as well.
Note that this claim is distinct from the claim that (due to general economic theory) it's more beneficial for the AIs to trade with us than to destroy us. We already have enough citations for that argument, what we're looking for are arguments saying that destroying humans would mean losing something essentially irreplaceable.