There are several issues in Windows 8.1 with some mice in games - Microsoft admits

[geeteam]

Soon after Windows 8.1 launched in October, many users noticed that that playing some games with certain mouse products was causing a great deal of lag. At the time, Microsoft did not offer any comments on the matter, but a recent post on their support forums indicates they are aware of "several different issues" with using some mice in Windows 8.1.

The support forum post states that one of the problems is that the mouse cursor seems to move quickly back and forward when moving inside a game. Microsoft says, "This occurs in some games because Windows 8.1 handles the games’ checks for the mouse status differently." Another problem is when users turn off mouse acceleration "to make the distance on the screen match the distance you move the mouse". Microsoft says this may no longer work with Windows 8.1. Finally, the Polling Rate on some mice products may have a lower than normal reporting frequency.

The forum post indicates that Microsoft is looking into a fix for all of these problems but does not yet have a date when they will be implemented. In the meantime, Microsoft does have some detailed workarounds for two more mouse-related issues in Windows 8.1. One of them fixes a problem if a mouse may not be able to reach all areas of the game world, while the other deals with an issue where left-clicking with an integrated pointing device right after pressing a key no longer works. Microsoft also mentions that some users have achieved some success in older games and apps by activating compatibility mode. Again, the post has the procedure for turning this mode on in Windows 8.1.

source: neowin

[dMog]

does MS not realize that that gamers make up 60% or more of their base customers

[geeteam]

i believe they do; so they are really working on it - as the report states