As the title says, I've finally merged my Summer of Code project - icon and pixmap cache - into kdelibs.
Buildsystem changes are not done yet, I'll do them in the next days. Until then, you might see old icons after new ones are installed. If you really need the new ones, do touch -m $KDEDIR/share/icons/hicolor/. Then the cache will notice the new icons.
The pixmap cache is meant to make disk caching of e.g. pixmaps rendered from SVGs very easy for app developers. It's API is similar to that of the QPixmapCache and I'm planning to create a TechBase tutorial soon to make it's adoption even easier.