Curse, when you chose a Monday to post your comments in the WoW forums, giving notice that you were cutting off WoWMatrix from accessing your site, you were using poor judgement. Your post hit the wire just 15 hours before the scheduled maintenance (nightmare) that was Patch 3.1. You've said you didn't know it was going to be patch day, and didn't purposely choose that particular day to break the addo updating routine of a lot of WoW users. But the patch was coming, and we all knew it was going to hit soon. And we all knew it was going to be a Tuesday.
And we all know that Tuesday follows Monday.
You gave insufficient warning to us to allow us to do a measured, properly tested migration away from WM. Everyone just had to jump. I didn't appreciate that, and I know a lot of other people didn't either.
Add to this the fact that a great many of us were using WM because we run Macs, and your Mac client was by your own admission, a dismal failure. That's assuming it ran at all, given that it wouldn't run on PPC or pre-10.5 versions of OSX. You've asked that people look at your reasoning for what you're doing, to defend your actions. By now, I'm fairly sure that (agree or not), you've also looked at the perspective reflected by my comments here. I'm hoping that you recognize where you could have handled this better.
Having said all this, I wanted to let you know that I've been continuing to test WM, trying to understand why, as I mentioned in an earlier post, the mere fact that I launched WM caused a pile of my addons to be marked as "dirty" by the Curse Client. You've said it was because WM was rewriting parts of the affected addons' code. I had confirmed that there were changes being made, but my code-fu is pretty weak, so I didn't understand what the changes were.
Over on WoWI's forums, and on the Blizz forums, there are smarter people than me who looked into it, and *did* understand. Their words can be found at http://forums.worldofwarcraft.com/thread.html?topicId=16474160156&sid=1&pageNo=15 and http://www.wowinterface.com/forums/showthread.php?t=22697. Basically, WM was monkeying with the addon code to cause the addons to not throw errors, even though they were out of date. They were also modifying the copyright in certain situations, changing them from the author's intent.
That alone is reason to abandon WM (the site and the service) to its richly deserved demise. I really wish you'd have been able to show us what the linked messages above did. Had you been able to do so when you pulled the plug, I might have been much more forgiving of the timing and method you used.
As for the client software itself, WM still has some things to teach, and I've already posted my opinions on that. Hopefully, someone at Curse had a chance to read it.
So, your timing: work on that. Your client: keep working on that. Your defense of your actions against WM: drop that. No longer necessary. Anyone who can read the messages above who doesn't get it, can't be reasoned with anyway.