I haven't used eCollege or Blackboard, but I have used Moodle (as a student) in a couple of courses, and to be honest I found it to be a stunningly mediocre. If it really is miles ahead of everything else then the whole concept of that type of software probably needs to be radically rethought.
PS: I should add that this was a good 3 years ago, so great things may have happened in the meantime.
> If it really is miles ahead of everything else then the whole concept of that type of software probably needs to be radically rethought.
That's pretty much what I thought, reading that. The college I'm at right now uses Moodle, and while it gets the job done it doesn't do so particularly well. Might just be because of how the professors use it (there's a lot of variability in how useful it is between classes), but even in the best cases it's nothing special.
eCollege from the standpoint of an TA was absolute crap, we as students experimented with several professors with Moodle and found it MUCH MUCH better than anything eCollege had to offer.
PS: I should add that this was a good 3 years ago, so great things may have happened in the meantime.