Also having this problem. It happens across applications (Ableton Live, Numbers, Finder, etc). It happens whether I use a physical click-drag or a three-finger drag. It also seems to cause the current application to beachball.
There are some drag-drop actions that are fine, for instance using the drag selection rectangle in the Finder or Numbers (to select many columns of a spreadsheet). The drag-drop actions that appear to be problematic involve dragging an item, like dragging a file from one folder to another. When you go to drop the item, it stays stuck the mouse cursor, even if you switch applications using Command-Tab. Doing this with Activity Monitor open shows a spike in CPU use after releasing the mouse, so perhaps there's a bug in whatever action takes place that normally causes the drop to happen.
The best way I've found to get something un-stuck from the mouse cursor is to click a menu at the top of the screen. Unfortunately, I haven't found a way to force it to drop the item where I want.