What would you define, label, or recount as the main moral of The Taming of the Shrew?

It is important to remember that Shakespeare wrote The Taming of the Shrew in the late sixteenth-century. Hundreds of years have passed, and in that time, attitudes toward women and men have shifted immensely.
One moral of the play could be that women should submit to their husbands. Katharina begins the play filled with passion and enthusiasm. Hortensio tells Petruchio about Katharina, the older daughter of Baptista Minola. Her father insists that Katharina must marry before Bianca, her little sister, can marry. Howeever, no one wants to marry Katharina. Hortensio describes how she is

Renown'd in Padua for her scolding tongue.

Later, Grumio describes her as

Katharina the curst!
A title for a maid of all title the worst!

Katharina is known for defying the instructions and wishes of her father, who is expected by society to be her authority figure until she is married. She behaves in an unfeminine manner, being loud and threatening violence, when compared to other women of her time. Men (including Grumio and Hortensio) are intimidated and repulsed by her unusual behavior.
Petruchio decides he wants to marry her, for her money, and determines that he can force her into submitting to his wishes by punishing her when she rebels. He goes to extreme measures to force her to obey him. For instance, when they are traveling back to her childhood home, Petruchio looks up at the sun and tells Katharina,

Good Lord, how bright and goodly shines the moon!

Katharina, who sees that it is actually the sun, denies his lie:

The moon! the sun: it is not moonlight now.

He insists, again and again, that it is the moon. She continues to deny him. Finally, he tells her what her punishment will be if she continues to defy him: they won't continue to her home. He is willing to turn around if she will not agree with him.
From this point on, Katharina learns to submit to her husband, even when she disagrees with him. At the end of the play, Hortensio says of Petruchio (as he exits the stage),

Now, go they ways; thou hast tamed a curst shrew.

In other words, Katharina has learned to obey her husband's every wish and desire, whether or not she agreed with him. She learned to accept his words and to accept his instructions for her.
One question that remains unclear, however, is Shakespeare's intentions in writing this play. Is he simply trying to make his readers laugh at Katharina's nearly unbelievable change and Petruchio's over-the-top plans to get her to submit? Or, is he teaching his audience that relationships between men and women should look this way? Maybe, he is making the case for the opposite: that these gender roles are ridiculous. Was the play offering a moral that others should follow, or simply amusing people with a list of silly events?