Should I trade Pierre Thomas for Michael Crabtree ?

I can't say for certain as I don't know what else you have on your team, but based strictly on one-for-one value I'd say do it. Mike Crabtree appears to be on the rise with Troy Smith finally providing some level of competency under center in San Fran. As for Thomas, who knows if he can stay healthy and with Bush coming back will likely never receive a great deal of touches, NO does like to spread the wealth around.