That'd be pretty cool. A flag you could set (probably in head > meta) that instructs the browser to use a default padlock instead of a fancy EV name for display HTTPS info. That'd obviate the need to have two separate HTTPS endpoints for your app too. Combined with User-Agent verification you could infer what % of clients respect the flag and what % impact (if any) it has on their conversion habits.

Course I doubt browser vendors would be up for adding something like this. Would probably be a pain as the rendering code would be separate from the display of the overall chrome.