The example that I'd use to support the theory that the NFL is rigged is the '06 draft. Going into the draft, 32 teams had Reggie Bush as the top player in the draft, yet the Texans draft Mario Williams. Reggie Bush wasn't the player that the Texans needed, but as such a hot commodity, it made no sense for the Texans to announce to the world the night before the draft that they agreed to terms with Mario Williams. Some team had to have been willing to trade, yet they don't even wait to see if any crazy Ditka-like offers come in. If no good offers came in, they could still draft Williams.
I don't think the NFL dictates the outcomes of specific games, for the reasons that Joe mentioned before, but I do think that the NFL is powerful enough to give a present to a friend in need, i.e. the city of New Orleans. Before they drafted Bush, that franchise was on its way out of New Orleans, after they drafted him, more season tickets were sold than ever before. I think that the NFL gave a gift to the city of New Orleans. Why would the NFL do that? Maybe it was trying to make up for the fact that they screwed the Saints out of a home game following Katrina. (Personally, I've always thought the compensation picks were awarded in an arbitrary manner, but maybe there's a strict formula that I don't know about.)
With all of the money in the NFL, have you ever wondered why there are no owners like Mark Cuban, who are loud and out of control? I think its because the NFL has far more power than any other league.
Do I think that the NFL is rigged? I sure hope not.
As far as the NBA officials, that didn't surprise me at all. NBA officiating has always been questionable, and an official in the NBA has more power to dictate the outcome of game than the officials of any of the four major sports leagues. I remember reading an article after the story broke, and an anonymous GM or coach said that he was only surprised that it was that particular referee, because he thought that Donaghy was one of the better refs.