There are many things to love about the new KDE and the new Firefox. I have personally always preferred Konqueror for most of my web browsing for simple things like dragging an image from the browser to the desktop. It was not that I wanted to leave an image file on the desktop. It is just a quick way to grab something and use it for whatever I need.
With previous versions of Firefox, dragging an image to the KDE desktop produced an empty clipboard text box and no image. Now, icons on the KDE desktop are essentially gone, replaced with the Folderview plasmoid. Firefox 3.0 also allows for perfect dragging and dropping. I can drag an image not only into folderview or one of folder icons but also directly into Dolphin (file manager).
It just keeps getting better and better.
Other cool plasmoids: