Not to be a WotC apologist or whatever you call it, but most of those were supposed to be developed by an external developer WotC was paying to do the work - and they botched it completely.
This does also explain why communication about all this has been so sporadic and poorly handled: before, they promised things before they were available, and messed up horribly. It disappointed a lot of people, and as your post and others show, is still a sore point for many people (myself included). So now they only communicate on things they are absolutely sure about, and don't make advanced promises on release dates or extra features.
Is this the best way to handle things? I doubt it. But I prefer short-time announcements and actual products over being promised the world and getting squat.
Like I said, this is one of the "last straws" mainly because, as you put it forth, they've missed big time before.
Now, the MOST important thing to me, is that my non-book gaming is at the mercy of someone else. If they decide I log in from too many IPs (I use the CB from 4-5 different computers in a normal week, 2 laptops at home, 1 desktop at work and at home and at a friends) or for whatever reason, I am cut off.
I gladly paid 60+ bucks a year for the updates and Dungeon Magazine because I knew I could keep using that stuff. Now, I'll either have to go back to buying books - and the constant feeling of paying for erratad books - or find some other solution.
We tried playign with just the books, but knowing the amount of errata that had been processed and released has made the PHB a joke - not only for what HAS been erratad, but because enough has been changed that you NEVER know what's right anymore.
Now, that was a problem we could overlook, since we had the CB to handle it all. Now we won't. So, from today the newly instituted rule will be that we use only the old CB, effectively making all future updates (for me) useless.
Now, if it had been better implemented, then perhaps I as a majority-Linux user could've seen some use (the removed need to Virtualbox a Windows installation for example) out of it. Now, with Silverlight (4 of all version as well...) that's kinda screwed too.
So, it's essentially about the future usability of a system. I'm paying for a game, like ALL other roleplaying games, I tend to come back and replay older games. All the books I have, that we play from time to time, are still useful. The D&D books won't FEEL as useful. So it's an emotional, and personal, reason for disliking this.
That and the series of broken promises. Ditching the OGL still lingers...