Yes. Same issue happened to me. Sometimes clicking on the Cortana tile gives me a dark gray window/popup above the search box (what would normally be the Cortana popup), but nothing appears no matter how long I wait.
Clicking in the search box changes the color, but it reverts to its original state almost immediately and no cursor is displayed.
It worked right after I upgraded, but it seems to have quit after I plugged in a standard microphone. Unplugging it does nothing. I haven't poked around yet to find out what it was. I was hoping someone else had run into it and solved it already.