Hi Barry, true, I guess I could have been a little more verbose, but sometimes simple is best.
I do believe it is worth having a TV calibrated. Of course that ultimately depends on who is doing the calibration and if they know what they are doing.
I have had it done and would (will) have it done again.
The average cost for a good calibration is $400. I don't know exactly what they do, but whatever it is, they improve the picture I see.
Some words of advice; If they show up without special equipment (signal generator for the TV's inputs and a light meter are a MUST) send them away. Also, they should have a service manual available for your model TV. One more thing, if they start changing things without somehow recording exactly what they changed and what it was before they began, you better have high confidence in their abilities or you are in for trouble.
Cheers,