Opera currently has a just a couple of features that aren't yet in Google Chrome (such as Speed Dial) but is an almost exact clone really. Some of the menus have been changed and items hidden (try finding the 'find in page').
Previous versions of Opera tried out lots of innovative ideas but those ideas ceased at version 12.17 when Opera moved to become based on Chromium, as is Google's Chrome.
Personally I believe Opera 12.17 is the best browser ever as it is totally customisable (I even use my own button designs!). Shame it was discontinued and is now outdated.
I'm currently testing SlimJet, also Chromium based but which looks promising.