[ThomPete]

The main problem I see is that they have made it simple by removing stuff but leaving no room complexity and still making the look of it complex.

For instance the browser background is semi-transparent which means that yes the page will probably stand out more in some respect but at the same time they have no canvas to work with to make additions, allow for third party stuff. It will have to sit on top of that transparent canvas which will end up making it more complex.

The reason to normally use white, black or gray is to have a neutral background that almost everything fit's nicely into. Now any icon or button have to compete with whatever happens to be behind the semi-transparent canvas.

In many way's from the looks of this they are already maxed out on design debt.

Of course that might be reading too much into it from this screen shot as I don't know what their plans are. But my immediate reaction is it won't scale very well.

[iaskwhy]

In their defence, that's how windows usually work on (err...) Windows 7, apps usually have the top bar and sometimes something more where transparency is allowed (there's a system setting for setting the amount of transparency, or none).

I don't see a problem since the tabs are not transparent, just with a small gradient like Chrome, and it's probably not going to be possible to add things (icons from extensions?) to the main controls of the browser.