Depends mate... most animation for games is IK, but a lot of work for feature film is still done using FK.

I just find I can pose my characters better using joint rotation than moving the ik all over the place and sometimes get that nasty elbow flip=) The other thing about Fk you can get better offsetting in the elbows and wrists.

My last animation with the baseball oger was all Fk except the legs had IK.

I guess i like the pain of a little bit more work to have a bit more control...

Im working on a freelance job right now for a game and it all IK=(