Isn't it about time Apple updated the World Travel Adapter Kit?
Obviously you can't use the 15w adapter that we all use now, as there's no way to disconnect the plug.
So you have to use the smaller (cube-shaped), lower-powered 10w ones.
And sometimes that isn't enough power. I was on a trip to Germany last month, and I like to have my iPad display a clock (using an app) and play music at the same time. With the 15w plug, that works. But with the 10w plug, the iPad runs out of power.
So isn't it time for an update?