and I've read them from time to time over the years. They do change.

If you want to see a model -- I think Microsoft has the best that I've seen in terms of clarity and transparency. http://office.microsoft.com/en-us/business/office-365-trust-center-top-10-trust-tenets-cloud-security-and-privacy-FX104029824.aspx#Top10Features

OMHO this is the yardstick by which you should measure others. (That might change over time also.)