While it does seem to be a problem in the drivers, X11 is not crashing.
Just fine? KDE 4.5 and 4.6 (upcoming) crash on log in with nvidias drivers ver 260.xx.xx (on openSUSE 11.3 32bit?). Many other applications and applets also crash, particularly on 4.6 where krunner, amarok and search and launch activity are amongst the affected ones. This is one of the currently most reported bugs at the moment with a current dup count of 58! As if all this wasn't enough in 4.6 the window manager also almost immediately freezes until desktop effects are automatically disabled.
So basically when you try KDE 4.6 on openSUSE 11.3 with updated nvidia drivers what happens is. You can't login due to desktop crash. If you fix that by removing the offending applets from the config files. On login Krunner crashes and keeps re-spawning and crashing. If you manage to kill it then desktop freezes and if all goes well effects are disabled. And if you get past then you can use it... without krunner, effects, and some of its best applications.
I love okular. That said it doesn't even support pdf annotations.
You can annotate pdfs, but these are stored separately, so if you send it to someone else they're all gone. In all fairness the problem is actually in poppler and not directly in okular but in the end it does affect the later.
For large values of one, one equals two, for small values of two.