You can gauge how much they (or anyone for that matter) care by the response you get when you try and engage with them. In this respect, my past experience has not been good (no response to emails/queries/etc), but maybe that is because I am not significant to them as an individual.

When I compare this to the engaging experiences I find with many YC start-ups (http://www.socialbrowse.com springs to mind) and others (e.g. http://www.huddle.net and http://www.freshbooks.com), the difference is night and day.

Maybe this is just my experience. Still, I’d be more likely to provide sensitive information to sites I trust and that seem to ‘care’.