My car has an acceleration problem, possibly the throttle body or catalytic converter?

Nothing is wrong with the car. Listen to the radio.

Nope...it's your transmission. That's the sign of a slipping torque converter. Better start saving your shekels before it fails entirely. In the mean time, don't accelerate so hard, it won't slip as much and it will last a bit longer before you can't drive it. You might also put some fresh fluid in it along with a pint of "transmission medic".

If that is your 1997 Oldsmobile Cutlass Supreme from last year, I would agree it is an instrumentation problem. Not a good fit for your symptoms, but the Vehicle Speed Sensors were notorious. With the rpm dropping and mph climbing, I can't think of anything but a bad rpm reading... as Anonymous says, a tach problem.

When the cat fails it usually blocks the exhaust flow. This results in a significant lack of power throughout the range. Try a change of automatic fluid and clean/replace the filter.

Nothing wrong with your car. A slipping transmission will result in rpms increase without a gain in speed. Car probably just have a failing tachometer.