Kaepernick has played well the last three weeks, and adds a dimension to the 49ers offense Smith lacked: The ability to run the ball. When Alex Smith was hurt in the last Rams game, Kaepernick came off the bench to guide the 49ers to a tie. Since then he's played well against two strong opponents (Chicago and New Orleans), and Harbaugh decided it was time to pull the trigger. Young Colin would appear to be a better match up for the Rams? We'll have to see what Jeff Fisher comes up with to counter the fleet footed QB.