I don't necessarily agree that programmers as such differ from 'regular people'.
However, I do get the impression that this field attracts a larger proportion of certain personalities, or at least a more vocal minority.
If we ignore the subset that are basically only in it for the money rather than their love of programming (yes, they are programmers as well, but I often get the feeling they ended up in the field based on a coin flip, and might as well have become, say, mech engineers or accountants, and would be just as (un-?)happy in those fields), we are to some extent left with people that
- care about what they do,
- do it for fun, on their own time as well as company/university time, and
- enjoy learning new stuff.
These people tend to be the good to great ones, in particular if they also like sharing their knowledge and passion. The question, then, is whether these people have any other distinctive traits in common that set them apart from like-minded people in different fields, and I'm not really sure they do. Understanding of logic? Not really unique to programmers, but perhaps more common. Perhaps easily learning new programming languages indicates intuitive understanding of syntax and grammar? If so, we probably have more in common with linguists than any of us would like to admit, and I've seen enough crappy writers that were otherwise excellent programmers that I may have to doubt it. Good problem solvers, analytic mindset? Definitely not field-specific.
I'm starting to feel like I'm rambling, but basically, what I think I'm trying to say is this: Yes, there may be common traits among programmers. But these traits are also common within other fields, and not at all specific to programmers. However, they -may- rather be common to people who love what they do and do it well, no matter their field.
But that's just my two cents.