I think the question Is it a foolish security move to use Google for search or mail? may be off-topic, but I want to get your input.
In my opinion, this question is outside the kind of questions I can ask here, but is tantalisingly close to being useful. Related questions such as "What concerns should I think about before moving confidential/proprietary data to the cloud?" or "What should go into a service-level agreement?" would be useful, but this question stops short of being either. The question "should I trust Bob?" is not a question for IT security professionals, whether Bob is Google or my neighbour.
Anyway, you may want this kind of question to be on-topic, or you might want to edit it to make it more useful. So I'm not going to use mod-fu to close it before you've had a chance to discuss it here.