If the connection was using a forward-secret key exchange (like DHE or ECDHE), then no. Unfortunately it's common not to and browsers don't do anything to warn people that they're using a low-security mode.
FWIW, just now I went looking for a firefox plugin that reports (in a human-friendly way) whether or not the SSL connection for a page is using perfect forward secrecy (PFS).
I found "Calomel SSL Validation," which I am about to install. The PFS reporting only works with Firefox 25 and up.
Thanks for finding this. Calomel's website [1] gives much more information about how the scoring is done as well as security in general; very interesting.
