I notice that KDE doesn't "fully" eject removable media. E.g. in other OSes/DEs when I eject my flash drive, the activity light on the drive turns off. It doesn't in KDE (4.6). Likewise, when I eject my iPod the iPod menu can be accessed even when it's still plugged in charging. The same is not true in KDE--it still shows a "do not disconnect" warning.

Is there any way to "fully" eject a device, say, from the command line? And why doesn't KDE fully eject in the first place from the device notifier and dolphin?

KDE simply asks the underlying device framework (HAL in KDE 4.5 and earlier, UDisks/UDev in 4.6 and later, unless an environment variable is set) to unmount the device. It is up to the framework to eject the device completely, if it is so desired.

I'm not sure I get your response. If KDE is asking the framework only to unmount, maybe it should be asking to fully eject. What does the framework itself have to do with whether KDE asks for an unmount rather than an eject unless there is a single command issued for device removal and the framework decides whether a removal is an unmount or an eject.

In any case, is there a command line command I can use to issue a full eject?

I don't know sufficient information regarding the exact capabilities of either framework, but as far as I know, any modification of this behaviour would likely need need to take place on the framework side, or inside kdelibs itself.