It might have a dismissive or mocking connotation, depending on the intention of the person using it. I guess in the worst case, its use could be described as 'othering'
ps. Funny how fast all these vivid thoughts crossed my mind in less the 2 seconds.
That's nothing, though, compared to this: http://pinker.wjh.harvard.edu/articles/media/1999_02_02_newy...
http://www.theguardian.com/science/brain-flapping/2013/jul/2...
As an example: Stephen Fry uses it, and he is a.) a geek and b.) not the kind of person to insult people for that kind of thing - when he uses it he always just means that they're people doing something complicated that he doesn't know about.