The kill switch meant that any applications Apple did not approve of or were dangerous could be disabled remotely by Apple themselves, confirmed by Steve Jobs.
Google Android G1 Market terms of service clause states that if Google finds “a product that violates the developer distribution agreement,” it “retains the right to remotely remove those applications from your device at its sole discretion.” In other words, Google can delete stuff off your phone without your permission. At least, that's how a lot of people interpreted it.
That cursory explanation, while not entirely untrue, leaves out one important thing: the fact that the clause states a removal will happen only if a developer violates his agreement. But semantics, as we all know in this week of presidential debating, can be misleading -- so I turned to Google for a straight-talking explanation.