It's been some time since EFF released HTTP Everywhere extension for Firefox, but now they just released HTTPS Everywhere 3.0 which adds more than 1500 new sites compared to previous release. You can also download the Alpha version for Google Chrome.
EFF is expecting that HTTPS Everywhere 3.0 will
encrypt "at least a hundred billion page views in the next year, and
trillions of individual HTTP requests". What a big target that is, but i'm pretty sure it can be achieved since more and more people are getting more aware of security awareness, mostly data security.