Today marks a very remarkable and sad day in Disqus history, as well as my personal history with Disqus (which will be explained later). Before I get onto my personal feelings about the classic Disqus going away, I shall cover the news of what has happened today first.
Today, all websites with the Disqus commenting system installed that have not switched to the latest version of Disqus (called "Disqus 2012" back in the day when it was in beta; now just called the "new Disqus") has been automatically upgraded to the new Disqus. Techman's World and I myself has been using Disqus 2012 ever since it was released to the public (at least for websites to use; during the private beta only select commenters such as myself got to use it).
If you were a website owner or moderator that was a part of a site that used the classic Disqus, then you was sent an email months, and weeks ago about the change. Unless you have been living under a rock or you never checked your email for whatever reason, this change was coming and was generally expected ever since Disqus 2012 was even though of.
What I think
The move to the new Disqus from the classic Disqus was unavoidable. It was known that eventually the new product would come to replace the old, but it was only a matter of time. Right now happened to be that time. Not sure how long Disqus 2012 has actually been "finished" (as in, when it was deemed stable or otherwise sent out of beta), but the time frame for users to switch was probably a year or so, more or less.
However, I'll still the classic Disqus theme Houdini, which was on the website before the upgrade. If you can't remember quite what the theme looked like, take a look at this:
As you can see, I customized the font a little, as well as the background colors for the comment headers. Normal commenters were pale green, moderators were a bright green (although you'd see this very rarely), and the dsq-founder (Disqus site founder) was me. I also changed the background color of the post as button to white I believe. Oh yeah, and the "Add New Comment" and other thread headers were in the DBXLNightFever font, which if you didn't quite connect just yet is the logo font for Techman's World. Hehe -- you can even see that this photo was taken before I even purchased the techmansworld.com domain.
Here's a snapshot of Disqus 2012 back in the day, when it was still in development. Not really relevant to present day, but I just wanted to stick this in here anyways. The photo was taken September 23, 2012:
Just from the photo above, you can see for yourself how much Disqus 2012 has changed since it was being first developed. The photo below shows when Disqus 2012 finally added support for image uploading, and drag and drop image uploading. As far as the button themes go, this was my favorite. I wish Disqus would bring back the background of the Post As button in the photo below:
I have a vast amount of other pictures from when Disqus 2012 was in development, but let's fast forward to present day. Here is that same comment embed, in present day:
Well, there you go. Not only have you seen a little about how Disqus 2012 looked over its development cycle, but you have also seen the same embed snapshotted 3 times.
And finally, the farewell. The reason why this day marks history for not only Disqus, but for me is because I first discovered Disqus around the time Houdini was released. During that time I was nowhere near getting Techman's World started up (although it was kinda a thought). Houdini was a fantastic theme, and its CSS customization was spot on. I liked everything, even how elements were classified. Houdini for me marks an example of my CSS skills being put to the test (and while I was still learning CSS), and the end of a CSS customization in Disqus. If you were like me, wanting CSS customization for the new Disqus, don't hold your breath. Basically, it's not happening, at least anytime soon.
Anyways, farewell Disqus classic. Although your death brings many advantages to Disqus, you'll always be remembered.
Update: I posted the classic theme that Techman's World used with Disqus back in the day over on my GitHub repo of CSS Mods that I make. If you are interested you can visit the Techman's World test page and see the theme while the classic Disqus is still up using Stylish. Note that I will not be making any edits to the theme just for preservation purposes.