Well, I have both a Windows box ann a Mac, but I am in no way upgrading to Opera 15, at least not until they add back all the features that where the real added value of Opera (Bookmarks, shortcuts, mail, link, note, DragonFly, Grouped tabs,...)
Simple things like being able to do a "manual" request isn't even there.
One of the things that really strikes me though is that NO ONE complains that you can't add new search engines.
I've switch to Firefox, but it's not really what I want.