This is not intended to be a "which is better" thread, but rather a thread that will help me (and maybe others) to understand the differences and the best uses of each. For the record... I have both.

How are they alike? How are they different? What does one do that the other won't? What does one do better than the other? When should I get a cloud number instead of a google voice number? When is a google voice number the better option?