That's not bad at all, I would say, innovation always have critics, and I think that KDE 4 is the way to go. But I'm not sure if putting it in the 'stable' release of Slackware is correct. Many Slackware users are upset because of this, but let me point why I still love Slackware:
- Slackware is not only a desktop environment, is a system.
- If you don't like KDE 4, you can use XFCE or install GNOME.
- If you really like Slackware, is not because of his desktop, is because of his philosophy.
- System configuration, services, kernel, etc. Are still the same as in previous releases, if you are a user, you have to know something about these issues.
But I have to be honest, I don't really think that KDE 4 is ready for a stable release in Slackware, Slackware is a great system, that's why I use it. It's very stable and simple, you don't have treat with non-standard configuration files or idiotic wizards.
I really love Slackware, but not all users do the same things with his system. I'm a developer, not a desktop user, but even in those cases Slackware rocks!.