I'm probably the last to comment on the Gmail/cloud issue – and you already know my opinion of cloud computing – agnostic.
We find that almost anything in life is great…when it works. When it doesn't?
Where the mistake is usually made is in the assumption that things always work. We pick up the landline, expect the dial-tone to be there and are shocked if it's not.
If I wasn't an eDiscovery dude, I'd probably sell insurance like my grandfather. Maybe I learned something about disaster-planning by observing him.
If you're going to use the cloud, institute a backup plan and stick to it – or make sure your provider is doing so.
Oh, and don't forget to test it regularly, in order to avoid 'Chronic' problems – such as getting into a David-and-Goliath war with a 3rd-party like Google.