For what it's worth, I don't recall ever seeing karma=1000 as a threshold of any importance, either for myself or for others. I'm not sure the idea of a "real" member makes much sense either.

I suppose I make some distinction between usernames I recognize immediately and those I don't, which probably correlates pretty well with karma. And maybe between ones for which I have a reasonable idea of what sort of thing the user tends to post about, what kind of positions they take, how impressed (or not) I've been with their thinking, etc., and those for which I haven't. That probably correlates with karma too. Perhaps the first one is kinda sorta a bit like karma>=1000 and the second is kinda sorta a bit like karma>=5000 or thereabouts -- but those numbers are completely made up and the correlation isn't really good enough for them to make a lot of sense.