The ESRB has recently rated Punch-Out!! for the Wii, giving it a rating of E 10+.  In their rating summary, they also provide some details about the game:

Punch-Out!!

Platform: Wii

Rating: Everyone 10+

Content descriptors: Cartoon Violence, Comic Mischief

Rating summary: This is a boxing game in which players compete in boxing matches against a cast of colorful, fictional characters. While players can use standard boxing moves (jabs, hooks, uppercuts), most fights are performed in a comical fashion with an assortment of “dizzy stars,” “cartoony” sound effects, and slapstick signature moves (e.g., growling, dropping shorts, conking oneself on the head, twirling, etc.). Boxers’ faces show lumps and bruises after taking damage, and some knockouts are depicted in slow motion as players are sent flying across the canvass. One character flexes his pectoral and glute muscles prior to a fight, while another boxer belches during a cutscene.

Looks like it will be following in the lines of previous Punch-Out!! games, which is fine by me!

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