What happened to the hobby / non profit apps, blogs and forums that fill 90% of the web and my bookmarks? All of them have a login form somewhere. Tons of people already use secondary emails or throwaway emails, but these site owners now have to pay for SSL or have to upgrade their shared hosting to "business" or the like to get SSL included, or pay extra fees to install SSL.
If all they do is look for a password field that means pretty much any phpBB or wordpress blog out there is defacto "insecure" and the owners of those sites now need to find a way to get SSL on their (most likely)shared hosting. Mine is not free at all, it requires "installation" fees, plus "dedicated Ip" so in the end it cost near as much as just buying their SSL package.
At this point though it's very unclear how Google will find those "insecure" password fields. Does it honer the no-follow? Because last time I heard it's not useful to get a login form page indexed anyway.