Is there a way to tell what the rotation limit is on a particular servo? I see just about every statistic about them EXCEPT the rotation (90, 120, 180).
Or is it just assumed that the majority are 120-ish Deg.?
Most standard hobby types of servos can physically rotate ~180 deg. The actual rotation depends on the electronics driving the servo position. RC equipment may only rotate a servo ~90 deg. Most servo servo controllers can can drive the servos the full rotation range of the servo.
To go a little further most standard size analog servos can do 180°. Micro servos are generally limited to around 150-160° due to mechanical limitations in the final gear. Hitec digital servo are limited to around 160° but can be programmed to increase the throw to the full 180°.