Great move by Google
Actually, it's quite different from the credit card companies. The CC companies do it to save THEIR asses. I don't care if some fool buys a bunch of stuff with my card, it's not my money and I'm not liable. What ends up happening is I will buy a computer or something and the CC company denies it for MY protection. Or decide I'm not really traveling overseas even though I called to let them know.
This is a very nice move in one sense; in another sense Google can tell from your ip patterns if you are traveling overseas or if it is a hacker, which reveals a bit of their Big Brother knowledge. Overall very good, because it is 100% for the users good.