The two people that Toby and I hear say "yooman" the most are Seth Shostak on the Big Picture Science podcast and Robert Scheer, the liberal guy on the Left, Right and Center podcast. Alas, I cannot link you to any short snippets for examples; you'll just have to download one or the other podcast and hope one or the other says the word.
What we find interesting is that there seems to be a California connection between the two, although that may be coincidence (certainly a sample of 2 is not statistically significant). Although they both went to grad school in California and live there now, according to their bios, they were both raised on the other side of the country: Shostak in Virginia and Scheer in New York. (And their surnames both begin with S, although I'm reasonably sure we can discount that as a factor.)
Anyway, hopefully someone out there who reads my LJ/DW and who says "yooman" exists and will discourse upon the subject, so I don't have to subject you all to a phone post of me attempting to pronounce the word both ways to check that the people saying what sounds like "yooman" to my ears are just under-aspirating the H and hear it themselves!
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