Web App Tab Styles

Which tab style do you prefer; the traditional on the left, or the contemporary on the right?

I'm using the contemporary tab styles (right version) through the app where it's working great visually as well as informatively.

But, the nature of this tab system, with it's relatively large amount of tabs, addition of numbers and the 'action bar' with buttons, makes me think the the contemporary tabs are not clear enough that they are clickable tabs that will change the list below.

Would love some feedback!