There is a new bug that won't let the mouse to the other screen unless you move the mouse quickly across the monitor edge. Before, this would only happen on the corner edges to allow easier access to the charms and apps bar. Now, it happens to the whole edge.
These four videos demonstrate that the mouse stickiness issue happens in both desktop and metro mode and that it is inconsistent - only happening sometimes. I hope these videos help paint a clear picture of what is going on.
Desktop Mode
Metro Applications
Is this issue already known and will there be a hotfix, or is this a new feature?
November 12th 2014 Update
Mouse stickiness still a problem as of today for Windows 8.1. As of Windows 10 Build 9879 which was released today, the mouse stickiness is fixed! This mouse stickiness only happens when dragging a window around and is used to assist in snapping windows. Outside of this, the stickiness issue is gone! I think this was what Microsoft intended to do with the mouse stickiness, but I believe it was a hard bug to diagnose, but they finally fixed it!
November 2nd 2014 Update
Mouse stickiness still a problem as of today for Windows 8.1. As of Build 9860 of Windows 10 Technical Preview, the mouse stickiness bug/feature has started happening.
June 9th 2014 Update
Still no official word from Microsoft. I have found a fix, but it is more of a workaround. Just don't use any metro apps, and it should be fine. Very rarely you will get the stickiness again. If it does occur anyways just press WIN + P and click Duplicate. After all monitors are duplicated, press WIN + P again and then click Extend to go back, and the mouse stickiness issue should be gone.
May 16th 2014 Update
According to Shawn "Cmdr" Keene [MVP] at the end of page 2, this is NOT a bug and it is an intentional design. I hope that Shawn is incorrect and would like further verification by an employee of the Windows development team.
There is also a "fix" by editing some registry values, but this removes the mouse stickiness on the corners and makes it very hard to access the apps and charms bar in between monitors. I do not believe this is a fix to the problem.
May 5th 2014 Update
Still no word from Microsoft that this is a bug or feature.