My observations:

Most people in word have 1-2 documents open at once. Most people in text editors like gedit, kate, eclipse, VS have maybe 10 or 20 tabs But most emacs users have at least 80 or 90 buffers open! It's an interesting phenomena that I haven't seen elsewhere. Why is this? Are tabs too much overhead or does emacs have really good buffer management?

Not a criticism, I'm slowly picking up some emacs after 2 years of vi, and I'd like to understand more of the nuances.

There's a selection bias at work - emacs.

I haven't met many people who casually use emacs (other than those trying it out for the firs time, or giving it another shot, (or another, or another))

For those who really GET emacs, and think in emacs, it becomes their entire workflow - as they can automate everything from emacs, incrementally. Those guys that work with 80 or 90 buffers open didn't start out that way - they grew over the years to working that way by tweaking more and more functionality to bend it to their will.

You can extend lots of editors - but there's something about emacs and it's lisp nature that lends itself to this kind of developer.

It's because Emacs is one of the few editors where you can actually manage 90 and more buffers -- thanks to the fact that you can refer to them by name.

Exactly. To switch to a different buffer I don't pick it from a list, I just enter its name. Actually, thanks to iswitch, I only start typing a few characters that are unique to the buffer name. It's an incredably fast way of flicking between different buffers and it scales very well to a large number of files.

Also, hippie-expand will expand to stuff contained in open buffers.

That's because in many respects Emacs isn't so much an editor as an operating environment. You can do pretty much anything from/in Emacs if you're so inclined. If you know Emacs' lisp well enough you don't ever need to leave. Heck, Emacs can even make Coffee (http://www.emacswiki.org/emacs/CoffeeMode).

To view Emacs as an editor, while technically accurate is not necessarily a fair comparison because it does so much more.

I believe you may want to check with java programmers close to you. When using eclipse I usually have 30-60 files open, probably for the same reason emacs users have them: it's very easy, has little overhead and accessing the working set is faster this way.

The reason it does not happen with gedit & kate is that tab-based interface fall into uselessness with too many tabs, if they do not provide alternative methods of navigating them than "click on the right one".

IMO, of course.

Tabs are one of those design decisions where everyone else is doing it, so it must be smart. I don't bother with tabs myself, most of my projects are small enough that I can find the files in the file list on the side in TextMate, Eclipse, etc..

I think a smarter solution would be to put recently accessed files in that file list on the side, vertically.

Much the same as it does in TextMate, probably. As many tabs as can realistically be identified plus an extra drop down menu with all of the rest.

(But I use the project view anyway, because I also see tabs as pointless, and most other developers I know rely on things like PeepOpen or Cmd+T's file finder.)

Managable.

To expand on that: I really like the notion of tabs in text editors. I like having a quick and visual represantation of how many files I'm working on. It's also very easy to memorize where a certain file is spatially.

But then I'm a very visual person, if I can only see one file at once without knowing all the open files at a glance, I go absolutely nutters.

It just seems that a) you're not doing a very good job at staying focused b) your editor doesn't help you much managing all this chaos