Version:           20080630 (using Devel)
Installed from:    Compiled sources
OS:                Linux

After using plasma for some time I realized it only save settings on session close (logout, shutdtown, restart). This can lead to several problem and incovinients, for example:
 
- clashes on plasma/X/system leads to configuration loss
- user must save it session to save plasma settings, keeping recorded all the apps it is running, which may be underiseble. In my case, as I am lazzy to close the apps and keep the session the way I want it to be the next time I login (few apps loaded), I just restart X or run halt/restart directly (most of times). 

In my, at every operation on desktop, like add, remove, move, rotate, etc, the plasma settings should be saved, or at least on a timeout of a timer.