When I started teaching online using WebCT, it was on a brand-new server with a brand-new version of WebCT which was as new to the rest of the faculty guinea pigs as it was to me. Everyone had problems with it. Thus, my students were sympathetic with my own problems, only part of which were a consequence of the software's bugginess. The rest were because I was new to teaching entire courses online. (I'd run informal workshops online before that, but not using teaching software.)

By the end of the semester, however, I was comfortable with the environment. Sure, it was full of problems, full of bugs, but I'd learned to work around the worst of them. Yes, I had experienced the decimal point fiasco*, but at least WebCT 6 had electronic grading sheets, a feature of which I was exceedingly fond. In the end, it really was too buggy overall, and the university decided to give up on WebCT 6 in favor of the already well-established and long-in-use WebCT 4. This switch meant stability, and, for most, familiarity; except, of course, I'd only taught on WebCT 6 before, not its predecessor. It was going to be another new teaching environment, only this time, I was likely to be the only new user of it.

Now I've had several weeks of working with WebCT 4 - and it's not so bad really. My WebCT experience has been all about learning to work around the software package's limitations anyways, and there's a whole lot to be said in favor of stability and speed.

Speed
WebCT 6 - Reloads all on-screen data after every post read and every little change made. Slow.
WebCT 4 - Only reloads manually. Much faster, albeit easier to overlook new posts and course changes.

Grading Sheets
WebCT 6 - Yes! Even if they did break during the decimal point fiasco.
WebCT 4 - No. I miss them.

Discussion Boards
WebCT 6 - More cleanly organized. Much, much, much easier to grade. Slow due to auto-reloading after every post read.
WebCT 4 - Functional, with some nice features like the prominent "Reply privately" button. Unintuitively, threads display without the name of their author on the main discussion board page.

Assignments
WebCT 6 - Plain text submission option!
WebCT 4 - Attachments only. Clunky for small assignments.

Groups
WebCT 6 - Mostly implemented, very useful where available for use. Could be better done.
WebCT 4 - Indirectly, yes. Sort of.

Overall Course Configuration
WebCT 6 - Yes, but not so versatile. Exceedingly slow and clunky to reorganize organization pages.
WebCT 4 - Yes, and nicely versatile. Easy to rename, relabel, edit, rework. Speedy organization page changes.

Other features
WebCT 6 - Announcement board! Green stars on course menu to denote updated parts of course! Test student view built in.
WebCT 4 - Green dashes on main page to denote updated parts of course; nothing on course menu. Test student account comes extra (i.e. separate login) - but is useful as a way of sharing, of letting someone else look around the course and see what it's like.

* After a spring break software upgrade, WebCT lost track of all the points which students had earned after the decimal point. While each was small, several different sets of post-decimal point credits add up to several points overall, none of which should have gone missing in the first place, and all of which then had to be manually reinstated.