I have a laptop with IE9, and just received a Lenovo desktop which I obviously upgraded to IE9... The thing is that sometimes when entering a reply in the Quick Reply box (the text only box under the forum replies) the cursor seems "stuck" and won't move when I press the arrow keys within the box.
The funny thing is that the position seems to actually change, because if I start typing the new characters will appear where I'd expect the cursor to be after the movement - it's just the cursors not moving on screen.
This happens in two different machines for me - it could be some add on I have on my systems for example...
This problem doesn't happen in a full reply, where the rich text editor (TinyMCE) is in use.