Tarampa Studios (5/19/2015)
Cinema4D has an excellent cut-n-paste too... it lets us copy any keyframes from one character/prop to another...
That little bit should be working now, so it's a start. You should be able to copy "same kind" of keys from one item to another, meaning you can copy a transform key from your cube to your sphere, etc.
I used to have a little daydreams of implementing a way to copy from project-to-project when the Python support gets released, but it's going to be way to limited (initially) to do anything even remotely close to that. So we ask, and wait, and ask, and wait...