Reasoning behind this.. Your display is like a lens into the game world. It takes up some arc space of your vision, and through it you can see some different arc space of the game world. The arc taken up by the display depends on the size of the display and how far you are from it. The arc of the game world presented is controlled by the game's FOV setting. You can think of the ratio between the two as the strength of the lens. Change the ratio too much in one direction, and things start to get stretched/distorted like looking through a fish-eye lens. Change it too much in the other direction, and it feels like you're running around looking through a telescope or binoculars. In fact, changing the FOV is how most zoom effects are done in games, like looking through a scope. One of the big knocks people have against ports of console games to PC is that the FOV is too narrow, and has that feeling of running around through a zoom lens. Why is that? Let's do some math. In this example I'll use my 22" PC monitor compared to my 55" TV. My eyes are about 24 inches away from my PC monitor and about 7 feet (84 inches) away from the TV. To compute the arc space taken up by a display, imagine a right triangle where the square angle is in the middle of the display, another angle is at a corner of the display, and the last angle is at my eyes. The vision arc inhabited by the display is double that last angle. Compute that angle by taking the arc tangent of the opposite side (half the display size) over the adjacent side (distance from eyes). 2*atan(11/24) = 49.2 degrees for the PC monitor 2*atan(27.5/84) = 36.3 degrees for the TV In order to have the same feel while playing on the up-close monitor, I need a significantly higher FOV. Since people use various sizes of monitors, anywhere from 15" laptops to big 28"+ screens and 3-monitor spanning setups, it would be best if everyone could customize their FOV to what feels right. There is no proper one-size-fits-all number here. The narrow default FOV (by PC standards) and the lack of configuration support is an immediate turn-off for many people accustomed to PC shooters. It's like having a big "CONSOLE PORT" sticker on there, and people who spend big bucks on gaming PCs despise that.
Yeah, an actual FOV slider built into the gui would be nice.. that would net you a LOT of respect from a LOT of people.... Including me.