The European Commission is trying to push for something like that, but I don't know if it's going to be anywhere as "strict" as what you suggest. It may be just something like C, B, A, A+, A++ ratings for security, which wouldn't be too bad, unless what's behind those ratings are really some inadequate rules.

SSL Labs' HTTPS ratings work because the developer of the test is also constantly tweaking and optimizing for current "best practices", and the ratings are not too far off from what the sites should be rated at in terms of HTTPS security.

http://www.euractiv.com/section/innovation-industry/news/com...