I get sick playing FPSs on my computer at anything above 90 FOV. I remember playing an XBox shooter, might have been Time Splitters 2, that seemed to be at about 110 with no option to change it. Couldn’t play.
Almo, via Kotaku
Setting a reasonable default FOV helps to reduce simulation sickness, but a single default can’t take into account size of screen or distance from screen, which are both significant factors.
Not everyone has the option of adjusting their viewing distance, so allowing FOV to be configured helps to avoid simulation sickness, which can be extreme, resulting in strong enough nausea and disorientation that play duration in excess of a few minutes can become impossible.
It is a greater issue on PCs than consoles due to the greater variety of screen sizes and viewing distances, and easier to implement on PCs too, due to more flexible frame rates.
More information: FOV in games (video)