Start menu -> All Apps -> Right click on a folder... does nothing. For some reason. Instead, you need to open the folder, then right-click on something in it.
So far I haven't had any real bugs since booting, but I've had no end of little "stuff clearly didn't get finished here" bits and pieces. One of the least polished overall user experiences I've seen. This is clearly "landing hot".
Here's another fun one:
Windows key to open start menu -> Use keyboard to navigate. Works fine. Up, down, right to hop over to the pinned apps on the right side of the start menu. Yay. Now go to a program in your most-used that has a jump list (Chrome, Steam, whatever). Highlight it by navigating to it with your keyboard. Press right -> highlight cursor goes from program name to jump list arrow. So far, so good. Now press right again, assuming cursor will move to pinned apps on right. Nope. Just stays there for some reason.
Here's another one; open the start menu, open a jump list from any of the left-hand side options (File Explorer is one). You can open it with either a mouse or by pressing space or enter on keyboard. Now the jump list is open. Press up or down, keyboard navigation of jump list works. Press left to go back to top-left menu? Nope. You can only press escape. Try to launch a program from a jump list. Press space. Doesn't work (why does it open the menu then?) You can only open the app by pressing enter.
Here's another one: open the start menu, start navigating with keyboard. Now start to type an app name, like you would to search for it / launch it. Doesn't work. You can only type to search if you haven't used keyboard navigation.
Here's another one: Search for something. Now, how do you get back to the Start menu? You can't use keyboard navigation, because none of the left-hand items get you back to the start menu. You can't just back out of your search by erasing what you typed, that just gets you to a blank search page. If you press escape, that closes the search menu. So Winkey->Winkey or Esc->Winkey is the only keyboard way to navigate back.
Here's another one: Why does the start menu font and UI have nothing to do with the search menu font and UI?
Here's another one: Why does every single context menu in the system have a different font, padding, colour, and basically no options in common?
Here's another one. Open the start menu. Press space. This makes you search. Okay, now open the start menu again, use keyboard navigation to go to an app on the right side of the start menu. Press space. This opens the app. Okay, now open the start menu again, use keyboard navigation to go to an app on the left side of the start menu. Press space. This does nothing. Okay, now open the start menu again, use keyboard navigation to go to a jump list, press space. Opens jump list. Okay, now use keyboard navigation to navigate the jump list, press space. Does nothing.