I'd say it's an error to give weight to any particular highly-improbable scenario without any evidence to distinguish it from the other highly-improbable scenarios. Here's why.
There is a nonzero possibility that some entity will acquire (or already have) godlike powers later today (as per your "I am a god" definition), and decide to use them to increase utility exponentially in response to a number derived somehow from an arbitrary combination of actions by any arbitrary combination of people in the past and the ever-moving present (and let's remember that the requirement could equally well be "condition y is met" or "condition y is not met"). I can't figure out a way to make the number of permutations actually infinite, but considering the negative as well as the positive options makes them cancel out anyway - we have no reason to believe that my posting this comment is more or less likely to trigger a utility increase than my (hypothetically) not posting this comment. The theoretically-possible outcome (huge increase in utility) does not depend on our actions in any predictable way, so there is no reason to modify our actions on this basis.
This leads to the following rational 'conclusion' (specifically considering this issue only) about taking any particular action, on a scale from -1 (definitely don't do) through 0 (indifferent) to 1 (definitely do):
±1/n, n->infinity
(Edit: Actually, this should just be 0. I should lay off the maths when I'm tired.)
(where n is the number of different possible sequences of actions which could possibly trigger the utility increase, and n therefore is unthinkably huge and continues to grow exponentially with each passing second)
Alternatively:
There is also a nonzero possibility etc etc decrease utility etc. etc. Every scenario which could lead to massive increase in utility could instead lead to massive decrease in utility, and we have no way to determine which is less likely.
Tim, you want "a good reason not to be jerked around by unlikely gods in general". Personally I much prefer my first answer (and I suspect you will too), but my alternative answer offers a much more concise rebuttal for any claim of infinite utility increase from an unlikely god:
"Your unlikely god will grant arbitrarily large increase in utility if I take the specified action? Well, my unlikely god will wreak arbitrarily large decrease in utility if I take the specified action. Give me evidence that makes your god and its claim of positive utility more likely than my god and its claim of negative utility, and we can talk - until then the probabilities exactly balance out, so for now I'll just carry on regardless.
I think the key here is qualification - Robert Morris avoided being wrong by not stating things unqualified unless he was sure of them, whereas the failure mode for rationalists is not expressing an idea at all unless fairly sure of it.
We want ideas to be shared before they're well-supported, because discussion is generally the best way for them to find support (or disproof) - we just need to signal the uncertainty when we introduce an idea.
It's much like what I've been taught in analytical chemistry - every number has a stated uncertainty associated with it.
We're working on that.
I think you're falsely assuming that "Africa" is a single monolithic recipient for that "sea of resources" - that ignores both the spectacular variation between and within African nations, and the difference between resources given to a corrupt government aand resources applied by non-government organisations for the benefit of people there.
I think it is fair to say that the staggering sums of money given by Western nations to African governments has been at best a complete waste of money - in fact I consider that money to have caused significant net harm. It props up corrupt regimes, increases and strengthens class differences, and generally results in increased oppression and widespread misery of various kinds. Your argument applies very well to this - "Africa" does indeed receive billions of dollars, and there is indeed something broken (most of the governments receiving the money).
This argument does not apply to the international NGO's working in Africa. Some of those organisations are short-term oriented and thus arguably pointless in the long term, but some are not. A classic example would be Kiva, which offers micro-loans for people to start small businesses to support themselves and family (incidentally not just in Africa) - there are a fair few organisations doing things like this, and it is "teach a man to fish" rather than "give a man fish". These initiatives, when they work right (which they often do) help lift Africans out of poverty and put them in a position to do something about their own future (and Africa's future). A lot of worthwhile initiatives centre around education, for instance, for fairly obvious reasons.
I think you're conflating "intelligence" with other concepts such as education and good judgement (which are what's actually needed here). Rephrased like that, it becomes obvious that a much more practical action is to fund and organise education of African people - give them the means with which to figure out the solutions to their own problems, but now rather than post-Singularity. Add direct financial support (eg. by Kiva or Grameen etc) in order that these now-educated people have the means to implement their ideas, and we have tomorrow's solution today. This is currently happening, but all we tend to know about Africa's current situation is an assortment of dramatic bad news merged together into a highly misleading narrative. To give you some idea of how significantly our perceptions differ from reality on this matter, here's a TED talk from from the incomparable statistician Hans Rosling 4.5 years ago: http://www.youtube.com/watch?v=RUwS1uAdUcI - feel free to poke around for more recent presentations and data, of course, but even this old one is an eye-opener.
I'm not saying that investment in education and entrepreneurship in Africa is necessarily the most effective use of resources from a strictly utilitarian standpoint - what I am saying is that you have not presented a strong case for African investment not being a worthwhile use of resources. Personally I regard your argument largely as an excuse to not feel guilty about distant suffering, but that is just an unsupported opinion.