omeletpants makes a perfectly fair point in that people should never plunk down the money for a calibration simply because they think that it's what they're supposed to do in order to achieve video nirvana. However, I think that there are an equal if not a greater number of people than those who are under the impression that a calibrated set is dreadfully dull and dim and that they're required to view their television in total darkness in order to appreciate the results.
But regardless of which side of that fence that they reside, consumers should absolutely educate themselves on why calibrations exist, why their TV would benefit from it, and what the end result would look like before deciding whether or not to make the leap.
And I strongly disagree with the notion that only a small minority of people would appreciate a properly calibrated TV. Like I said earlier in the thread, the average consumer doesn't even know that such a thing exists. If everyone were educated on calibration and then a magical button pressed so that everyone's set was made accurate, I can't imagine that the vast majority would want to reverse the procedure.
If you've dropped some decent coin on your HDTV, have read up on calibration and what it entails, and think that it may be of interest to you, then I'd say it's absolutely worth trying once. If the end results are not desireable to you, then you know that you'll never need to worry about it again. Adjust the settings to your liking and be happy.