Opera One Browser Adds Vertical Tabs - Should Safari Follow?

Opera One browser just pushed an update adding a Vertical Tabs option that moves the tab bar from the top of the window to a resizable panel down the left-hand side. The feature aims to solve the perennial horizontal tab problem where too many open tabs makes each one shrink to an unreadable sliver of the webpage's favicon. By contrast, in the vertical layout, page titles always stay legible.