Well said Sam!
Perhaps we should expand on this page? http://docs.moodle.org/26/en/Increasing_privacy_in_Moodle
Why so called "free" 3rd party web services aren't free. What they can tell about us from our metadata (it's scaaaary!) and how this has got some people into trouble or awkward situations, e.g. the family who discovered that their teenage daughter was pregnant because their targeted advertising suddenly changed or people who've been raided by the police because of doing legitimate online research into terrorism or child pornography related topics (psychology and social studies students beware!).
For the future... we can only speculate based on what's already happened; employers demanding access to social networking data or using 3rd party services that "scrape" and mine data from G+, Facebook, etc. Banks, insurance, and medical insurance companies using services to vet loan, mortgage, and insurance applicants, insurance claims, etc. and basically using algorithms that apply the principle of "guilt by association", e.g. if your "friends" are poor, default on debt, sick, politically active, etc., then you probably are too. In a court of law this would be gross misconduct and inadmissible... but corporations aren't bound by those laws and can do this stuff in secret.
Advice for network sysadmins
Install NoScript and share whitelists (also good for security), cookie managers/munchers, TrackMeNot, etc.
Advice for webmasters and Moodle admins
Secure and private analytics, blocking search engines, etc.
Advice for teachers
Alternatives to 3rd party web services and why we should be using more free and open source software instead, e.g. ownCloud.org is increasingly supporting OpenOffice and LibreOffice doc formats for online editing (alternative to Google Docs and Google Drive).
Advice for learners
Which browser plugins to install, why we should use different browsers for different sites (partitioning/sandboxing). When it's advisable to use anonymising techniques, e.g. TOR. ANd don't put personally identifiable information (PII) online, e.g. email, phone numbers, addresses or parts of addresses, birthdays, etc.
Human rights and privacy advocacy campaigners and organisations
Richard Stallman's website (loads of info about what's bad about Apple, Amazon, Google, Microsoft, Skype, Facebook, DRM, etc. and some friendlier, kinder alternatives).
On the Moodle.org Security and privacy forum https://moodle.org/mod/forum/view.php?id=7301, predictably seem more concerned with immediate security and "saving their own ass" than the bigger picture and (other people's) problems further down the line.