Certificates serve two purposes:
1. 2 Way Encription. (Security)
2. Verifying the Site's (Identity).
Microsoft and Mozilla's Brain dead Idea of putting HUGE warnings up for "Self Signed Certificates" means that people cannot just choose security. IMHO a certificates primary use.
By using "Authority" signed Certificates people are "Trusting" someone else to secure their data. - and paying a large(ish) sum of money for this service.
I would Prefer if every site had a self signed certificate. and a Separate name verification. - which did not require my stupid browser to click on BIG WARNING MESSAGES. before getting to the site.