Hi, I'd like to make a few comments on von Neumann considering I've spent some time reading around about him.
First of all, on the biography. So far for me the biographies written about von Neumann have two key problems to me:
1) They avoid his mathematical work and focus on his work in game theory, computing, nuclear weapons, etc. I find this a bit problematic because despite all his other achievements, von Neumann was fundamentally a mathematician who applied his skills in mathematics and logic to other fields to great success, however before all this he first made many substantial contributions to pure mathematics. Now the question is how can one author cover these broad areas that von Neumann contributed to at a reasonable level? I'm not really sure it can be done, even von Neumann's colleagues themselves weren't fully aware of the extent of his work. For example I remember reading some interview of one where they said he never made any contributions to number theory, yet von Neumann early in his career did publish at least two papers on the field, one on algebraic number theory and another on transcendental number theory. So perhaps multiple authors, each covering their specialty would work better if they can make their chapters weave together nicely. Another problem is what level should it be. I personally would like it to be around STEM major level mathematics so you can properly introduce some concepts however I understand most authors wouldn't do this because it decreases their possible audience.
2) Not much research is done into what technical work he did in defence and for private companies (particularly IBM). From the biographies I've read they all happily cover how von Neumann was this greatly respected figure and how he lead this committee and that committee and how on his deathbed he had the chiefs of all the armed forces and the chiefs of staff there too but that isn't really covering the actual technical work he did there (a good reference for his government consultancies is `A Fiery Peace in a Cold War`). He obviously consulted widely in the military, CIA, NSA, etc, military establishment in general but in terms of technical work not much is there, presumably because all the records are hidden or classified. I can understand why some of his work even today might remain that way (particularly his work on nuclear weapons) but I've yet to have seen anyone try send a FOI request to various agencies and see what they can fish out given that he died over 60 years ago. He did spend a lot of time on these things post WW2 so it would be interesting to see what he did actually contribute to beyond his position on committees and advocacy.
I notice several other comments on this page I think I can make a educated comment on as well.
First about his views on communism. As a child in Hungary von Neumann lived through several revolutions, one communist and another antisemitic. He was at risk of attack from both groups, from the communists for being part of a wealthy family and from antisemites and far righters for being a Jew. Safe to say I can imagine this ordeal while he was a teenager didn't leave a good taste in his mouth, especially as he had to move around the country to avoid being attacked and potentially killed. His remark about bombing them at a certain o'clock was from 1950, just as communism was being spread quite forcefully through violence around Europe and you can imagine why he wanted to prevent this from happening, especially considering the USA would probably lose a conventional war at this time, however they still did maintain a monopoly on nuclear weapons (for a short period). I would also like to note that for whatever reason he seemed to believe nuclear war was inevitable, and made an admission on his death bed that he believed nuclear war was "absolutely certain" to occur in the future and that everyone would die from it. This might help explain his comments if he sincerely believed nuclear war was inevitable anyway (luckily it wasn't). I would also note that he visited Moscow for a conference in 1935 and I'm sure he had many friends there, so views that he wanted to exterminate civilians for the sake of it or whatever would also be clearly wrong.
Second on the Kyoto scenario. Despite wikipedia claiming so, scanning Macrae's biography shows no indication that von Neumann had Kyoto as his first choice, but rather one of 4 cities he voted for. From what I understand the targeting of Kyoto was first added for technical reasons, and did in fact have strategic value, however the targeting committee did also note that perhaps a city full of intellectuals would more likely appreciate the significance of the bomb and hence advocate for a more peaceful solution (http://blog.nuclearsecrecy.com/2014/08/08/kyoto-misconceptio...).
Third on the good upbringing argument. A good way to see how special von Neumann was compared to other mathematicians and scientists is to get their opinions themselves, unfortunately most are long dead however several history projects do include information on this. This [1] is a good example. Basically everyone who mentions von Neumann notes that his speed and rapidity is bar absolutely none, however one of them (Edward McShane) does quote fellow Princeton mathematician Solomon Lefschetz in saying that they paid too much respect to von Neumann because of his upbringing and in particular he had the finest tutoring by Hungarian mathematicians as a child. However a counterexample to this is simple. If it was just that, then why has no one like von Neumann come up in the past 100+ years? Especially considering how material conditions and access to information have only improved since the early 1900s when von Neumann grew up.
[1]: https://web.archive.org/web/20011126182532/http://infoshare1...
Overall I think von Neumann is someone particularly unique. Not because of his creativity, nor because of insight, sure he may have had these qualities but so did many other people. What is unique about him is his speed. Looking at some of these interviews on several occasions it seems that von Neumann was literally making up new proofs for some theorem on the spot. Whether he thought about them beforehand or whether he did truly make them up on the spot is of course in question, but it seems he did it often enough one might could not be blamed for believing that the latter version is what he really did. I would also note a strange fascination that HN seems to have with von Neumann, as I see him here quite regularly and I can understand for some the worship is excessive, so it is important to note even someone of his caliber can make mistakes, the most important one I believe is already mentioned in this thread which is the mathematicization of the measurement problem. Everyone can make mistakes, and absolutely no one is immune from this.