I have the new bluetooth keyboard so the impact is minimal.
It impacts me in the following way: because the device recognises the keyboard isn't attached the surface starts behaving like it's in surface mode. Then the track pad becomes 'stuck' and doesn't let me scroll but lets me move around the screen and touch things, but won't allow me to press and hold with the usual receptivity that the track pad would have when it is detected.
Even when I do detach and re-attach it, it takes a whole 10-seconds before the SP11 stops recognising it as connected again and starts behaving in surface mode.
I love my device, it's actually the perfect hybrid, but this small thing is really bugging me because it renders my track pad useless at random times throughout the day.
I know it's in surface mode because apps like word, for example, will switch to the drawing tab, or the screen will change display sizes and turn into surface mode.