can you animate the visibility of an object in maya?
 

Or in other words, let's say I have an object in an animation that I want to "fade" in, from 0% opacity to 100% opacity in, say 15 frames.

I'm a Flash guy so I'm thinking in that mode--so for you Flash guys, essentially what I'm looking for is a timeline-based tween using 2 key frames.

Any help?

visability on an objects shape node (the one you see in the channels) is a boolean and usually not animated and is more accurately the display of the object rather than how visable it is. when it is off the objects shape will litterally not be in the scene.

If you want a fade it is done using the matterial, simply keyframe the transparency of a matterial over time along with any reflective attributes may still cause it to be visalbe e.g. specular color.

Awesome feedback! Thanks for the explanation, that helps a lot.