Did nobody RTFA? Despite the designed-to-induce-panic headline, The screenshot in the article actually looks more like Google Chrome (which also has no menu bar, and it works pretty well) than Microsoft Office.
Even if they *were* going with something like the Office ribbon, think for a moment about what that means. Look at a traditional menu bar from a usability perspective, as though it had never been done before and someone had just invented it. You've got a row of tiny buttons across the top of the window, just big enough to show their names. You click on one, and a row of small, temporary text-labeled buttons (the menu) appears underneath, in a simple row. You have to go down to the row you want and click it (or hold the mouse down and release it, which is awkward, but saves a fraction of a second once you're used to it). Then, all these buttons (the menu items) disappear. It's kind of awful, really.
Now, look at the Ribbon. Once again you have a row of text-buttons like the menu bar, but this time (in office, at least) they're a bit bigger. Once again, when you pick one a set of buttons appears underneath, but this time instead of a linear column of plain buttons of all the same size and shape, these are laid out however the UI designer wants, for (theoretically) maximum usability. There's room for a lot more buttons than in the menu, and best of all they don't disappear every time you choose one, which means that you can learn their order and position just by glancing up at any time. And once you've used one, you can use another from the same menu without having to start over and click on the header again. It's clearly (if done right) better than a menu bar in every way but one: it takes up more screen real-estate. (Yet oddly, nobody seems to complain about that one real and fundamental issue, which I think maybe isn't as big a problem as it sounds like.)
Conclusion: ribbons are pretty cool, even if Microsoft's implementation needs a bit of work. Menus work ok and we're used to them, but they're kinda gross. All these people complaining about buttons on their ribbon running around and changing on their own may be drinking too much coffee.