So far, the new version of Opera is REALLY stripped down... it's basically reskinned Chrome with half the functionality and a new icon. Can't change the default search engine, bookmarks don't sync, it's... pretty much pointless. I'll be curious to see how they differentiate themselves moving forward. It's always been a niche browser for enthusiastic power tweakers... they've thrown all that out. Thus far, the only reason I can think of for using it in the future is sync with Opera mobile, if you use that. Of course, that's purely speculative because even that doesn't work right now.

First preview of the Webkit based Opera 15 is out.

So how different is Opera 15 from Opera 12.15, the latest stable desktop version? You may not notice that many changes on first glance but there are many if you look deeper.

• The icons in the bottom bar including the zoom slider are not there anymore.
• You cannot open a small sidebar panel with often used icons anymore.
• The appearance menu is not available anymore. It seems that you cannot customize the look and feel of the browser anymore. This includes toolbars, icons and their position and visibility in the browser. No tabs on side.
• The browser settings are limited.  Examples of removed preferences include selecting helper applications for selected programs, font selection, all tabs options and file type actions.
• The opera:config page is no longer available.
• Chromium developer tools are now used. Bye bye Dragonfly.
• Opera Notes is not available.
• Custom shortcuts and many mouse gestures missing.
• Bookmarks not available yet.
• No RSS.
• Opera Extensions are not supported.

[Source]

I'm going to be playing with it today... we'll see how it goes. The one thing I'm excited about is M2 becoming a standalone mail client -- that's something I've really always hoped for.