this QB situation in SD is going to be awkward for a while... they would like totrade Rivers now, but he is worth little because of the experience factor, and we don't know if Brees will repeat his success (though I am optimistic for him). Trading Brees away results in starting a rookie QB of unknown future.
I think they will trade Brees high, and get some compensation for him. They were awfully high on Rivers, so they might as well get a great deal for Brees, start Rivers, and have an ultimitely better team if they trade right. And maybe Brees can return to Texas... (his home state).
On a side note, why hasn't AJ Smith come under heavy offers from other teams?