I just performed zypper up (11.2RC2) and after restart all I got is a black screen (GUI is automatically started). Removing ~/.kde* “fixed” the problem. Luckily, desktop effects are turned off by default. Turning it on with OpenGL compositing type fails with the following message:
Failed to activate desktop effects using the given configuration options. Settings will be reverted to their previous values.
Check your X configuration. You may also consider changing advanced options, especially changing the compositing type.