So, if anyone is looking at this thread to find a solution to the copy/paste not working in PP 2010, I have discovered the solution- at least for my system. I had to employ the help of the SmithMicro troubleshooters to get the answer, which makes me feel a little stupid- since the answer was so simple.

 

In P7, the only way I could copy and past key-frames was with the Edit drop down menu. The keyboard had no effect. However, with PP 2010, the exact opposite is true. The drop down menu doesn't work, and the keyboard- which is my preferred method- works like a charm!

 

I haven't tried this with different layers, but I guess I haven't found layers to be useful with my work-flow. Perhaps someone can enlighten me on the usefulness of layers- because the way I tried to use them just made the whole animation process more complicated without any benefit that I could see.