2 things can cause this. 1 is not a problem. The other is a minor problem.

1. You're driving the car before it's completely warmed up.
-the idle speed is sometimes as much as 1000 RPMs higher when the engine's cold, and that can result in jerky shifts.

2. Your idle speed is set too high when the engine is warm.

I think Automatic cars are supposed to idle at 850rpms... but my service manual is nowhere in sight... you'll have to double check that in yours if the needle is any higher than that and the car's warmed up all the way.

You should flush/fill automatic transmissions every 30,000 miles ( or 48,280.32 "canadian").