I'm considering using the Google Contacts API for a webapp, but I'm worried that a user might have a bad experience that could be blamed on me.
I intend to use the data in a responsible manner, I could get blamed for somebody else's misuse of it. Has anyone else had this? What did you do about it?
Answer this question: Can you secure your webapp against all crackers out there? Are you more clever than any criminal out there?
If not, then the data won't be safe. Criminals will come up with ingenious ways to extort a revenue from data on the web. If I should ever have to apply for a new job, I could ask StackOverflow to create a CV for me -- they have all the necessary data but that's because I want it. So this is probably OK. But some sick mind may find patterns in my posts, things which I'd never have thought of -- word frequencies, length of posts, complexity of the answer, time of posting -- to deduct some further info which I didn't want to disclose.
So the better question is: Is the revenue (which you want make) worth the risk? If you don't get anything for the data except blame, why collect it?