<rant>I think we should all read 'the lunatics are running the asylum'.
I haven't looked at Moodle, but it sounds like it has a well-thought out design. We really have to focus on creating quality designs for what people most commonly want to do, and making the computer do the hard stuff. Unfortunately, the needs of the program design and the user design often are at odds, and it takes very careful and creative design to resolve the conflict.
We do have a great architecture, but that doesn't mean anything unless we take advantage of it with a great UI. We're getting better, but really that has to be our primary focus instead of a secondary one.
My grad school advisor used to put it this way: 'It doesn't matter if you have the functionality to do this or that in your program. What matters is if the user can find it before they get too frustrated and give up trying to find it.' I would add thta the user gets frustrated very quickly.
</rant>
We're moving in that direction, though.
By the way, a good example of a web-based UI, IMO, is www.evite.com
It's very well done.
