If you've been on HN for more than a couple of months, surely you have seen the horror stories that people post regularly. Having Google as a single point of failure for one's business seems risky. There are oodles of DNS providers out in the world that have real support mechanisms for escalating problems. At the bare minimum, when you choose to use Google for your domain's email and other services, keep the DNS off Google so that you have a path for recovery that isn't an empty void in the fabric of space and time.