There's not a lot of point to EV. Google and eBay don't even EV their primary domains; given what high-profile targets those are for phishing, the fact that they're not EV should tell you something about its utility as an anti-phishing measure.
As per [1], twitter does use EV certs, but not everywhere. It depends on the geographical location. The author of this article (Troy Hunt) never noticed this inconsistency, whilst he works in security.
Given that he never noticed it, and the fact that I've never heard of anyone else noticing it. I'd say that even when high-profile targets deploy EV, it still does nothing.
A possible exception might be banks. I've heard (I think in the HN comment thread of [1]) of people actually calling up banks asking why the name isn't in the green part of the browser. I know I check that address most often. I guess people are just most security aware when it comes to mixing the internet and money.
I recommend this presentation to help dispel a lot of misconceptions about phishing and how easy it is for even highly technically and security literate people to get phished:
