Always like the people who somehow think that Rivers has increased in value, or is even anywhere near as close to his draft day value. People tend to forget that the Bolts were the only team that thought Rivers was worth a Top 10 pick. Simply because he was taken at the 4th overall spot does not mean every other team values him that high. He's also sat the bench for two years and not seen the field. Why would the Texans even trade for a QB? They're going to pick 1st overall, they can just take Leinart.
The money issue that people love to bring up isn't that strong of an argument either. Yes I'm sure McNair would love to not pay $20M or so in guaranteed money, but the Texans are still making money hand over fist. He's not going to make a trade like that based on large part for monetary reasons. If he trades for Rivers, it would be because they think they're getting a superior player. Not having to pay any bonus money is, for lack of a better term, a bonus.