What is the difference between http and https when accessing Google Reader?

https is encrypted both ways. Portions of a page can be encrypted and not others, but your browser should (or at least can be set up to) warn you if that’s the case.

Cool. So, if I didn’t receive any alerts, and Firefox claims that “Your connection to this site is encrypted to prevent eavesdropping,” it’s not like certain frames are encrypted and others aren’t?

That is correct. (Assuming you haven’t turned of the warnings).

I imagine what they say about using https with Gmail is likely to apply to all of the Google cloud services (like Reader, Notebook, Docs, etc.).

I can’t find it written down, but I think Google would always use an https connection when handling initial authentication. (So, even if you access the logon page via http, it would actually send the credentials securely via https, and then the rest of your session would continue in plain old http.)

Cool, thank you! Maybe I should use WireShark at home and play around with it. Again, thanks, everyone.