Just had a very quick look - not impressed.
Opera is a very good example of what is wrong with free software - they spend their time tinkering and adding new features instead of adding basic functionality that is missing (perhaps because they don't realise it's missing because they only use their own product).
For instance, I still can't Ctrl-click to open a link in a new tab (I have to shift-click instead). Nor can I right-click the navigation buttons to bring up the history. That said, you can shift-click a bookmark to open it in a new tab now (not sure when they added that though). But I can't make minor changes to bookmarks by dragging or right-clicking.
Particularly stupid is the absence of the menu-bar by default (one company has a stupid idea and others feel the need to copy it - crazy). However, when you show the menu bar with aero active, it works but looks ridiculous. Either it should be drawn using aero methods or the glass area below should be made non-aero.
However, the most obviously stupid feature that needs to be changed has to be the "Closed Tabs" button all on it's own on the right instead of on the left with other navigation controls. And when you move it, it's slightly the wrong size and looks silly!
This might be enough to hold on to their 1% market share but not nearly enough to improve upon it.