Don't forget (all of you) that the Chiefs lost their best offensive tackle to Chicago (why does his name escape me right now?). Now that CLEARLY doesn't mean that their O-line is going to be worse this year than San Diego's, but it will diminish Priest's numbers ever-so-slightly.
On the other hand, I think Priest will retire after this season. He''s said that he considered retiring this season already, but decieded to play at least this year. Therefore, he'll be running for a ring. Tomlinson, on the other hand, only needs to run well enough that someone will pick him up once the Chargers can't hold onto him any more.