If you've upgraded to ADT 20, you may have noticed that your keyboard no longer works on inputs on your emulator. That is, when you have an EditText on the screen, typing characters into your physical keyboard doesn't register anything in the emulator; you need to open the soft keyboard to do anything.
The problem is that the emulator no longer assumes you have keyboard support by default. You'll need to add it yourself to the emulator and your keyboard will work again: