Its also worth noting that its very difficult to assess usability for a system that you've been developing. As with many popular software products, after a time you get used to them. Once that happens the UI limitations become largely irrelevant. Therefore if you've been closely involved with a systems development it becomes harder to spot the 'weak' points, because you are acclimatised.
I also noted the suggestion that we perform some kind of usability testing. I do agree with this is the academic sense, but what I think we might struggle with is exactly how we define it.
Let me use my favourite anecdote for this. I've used VI since I started university. Many people I know very quickly picked up emacs, or some even more elaborate development environement largely because of the all to familiar ' VI is hard to use, difficult to remember etc...'
One could argue that VI has poor usability/interface. However, some 8 years after gradutating and with a weath of tools and applications at my disposal, I still, ferevntly, use VI. I still haven't comne across anything more 'usable'.
I do concur with Don also in that I don't see ANY relationship between OS software and usability. I think its much more to do with that fact that a lot of OS software is not production quality (nor does it try to be) and therefore its unfair to lump all of it together as is it were the same thing.
Perhaps my earlier point explains why people think Microsoft is the 'way computers work'. Just like me and VI, most people are exposed to this first, anbd therefore the get used to it. This makes it easier to use it, and therefore, good UI or not, its easy.. and therin lies the answer. Perhaps usability is nothing to do with an objective measurement, but rather the compatibility with a de-facto standard.
Of course the danger in that argument is that we should probably make OACS more 'windows-like' if we want a widely accepted UI.(?)
Hmmm....
