One problem is that we might not know (what) it's sending to facebook, as we don't have access to the code to review it. Sure there's tools to analyze/reverse engineer the client, but that isn't really a practical option.
Opera users instead trust Opera on the security and privacy they claim to offer. This tends to work fine, as Opera have a good reputation for privacy, and they have not abused the trust of their users.
Facebook have, multiple times. Anyone who cares about privacy will avoid it purely because facebook cannot be trusted. Trust must be earned, and facebook have much work to do before they will earn the trust of many (if ever).
I'm not quite sure what it is, but when companies are large enough, people tend to be forgiving, as if their past sins have been cleansed without any good reason. People tend to misplace popularity with trust - if so many people are using it, can't be bad for you right?
Opera users instead trust Opera on the security and privacy they claim to offer. This tends to work fine, as Opera have a good reputation for privacy, and they have not abused the trust of their users.
Facebook have, multiple times. Anyone who cares about privacy will avoid it purely because facebook cannot be trusted. Trust must be earned, and facebook have much work to do before they will earn the trust of many (if ever).
I'm not quite sure what it is, but when companies are large enough, people tend to be forgiving, as if their past sins have been cleansed without any good reason. People tend to misplace popularity with trust - if so many people are using it, can't be bad for you right?