Dude, I know you're a hot shot . . . guy . . . who . . . apparently knows random things about the law, but . . .
From a Texas Court of Appeals opinion written less than three months ago, where a guy purchased hard drives that were mistakenly listed for $1 each; the website refunded his money instead of delivering, i.e., money had changed hands:
Perez v. Hung Kien Luu
November 1, 2007
"If prospective seller's misrepresentation is limited to an item's price and that misrepresentation is made only in a general advertisement, claimant must prove an intentional misrepresentation, to recover under the Deceptive Trade Practices Act (DTPA) for misrepresentation of characteristics of goods or services, or misrepresentation that agreement confers or involves rights." V.T.C.A., Bus. & C. § 17.46(b)(5, 12).BTW, the V.T.C.A. that the court cites at the end of that quote refers to Vernon's Texas Statutes and Codes Annotated.
So, to answer your question about who gets to define 'genuine pricing mistake', the answer is pretty clearly the retailer. If the retailer says it was a mistake, it was a mistake . . . unless the consumer can prove otherwise.
Oh yeah . . . I'm a 2nd semester law student