I can get Extended Validation for cheaper than Domain Validation, yearly. What are the differences between them?
EV SSL's can only be issued by those certification authorities (CA's) who pass independent audits for WebTrust, and requires standardized issuing criteria. Visitors will also see a very noticeable green bar in the address bar of all modern browsers, which is becoming more recognizable now that online banks are using them.
DV SSL's on the other hand require no more validation then just sending an email to the domain admin or technical contact listed in its WHOIS record with a link in it to authenticate the owner of the domain (similar to a website requiring signup validation via email).
This also provides additional reasons why many top CA's do not offer Domain Validated SSL's.