The ideal situation for any rookie quarterback would be coming into a situation where he didn't have to start right away. There are so many adjustments that a rookie has to make, and the speed of the game is so much different that it takes an adjustment period. In most cases a guy is going to have more success down the road if he is able to sit and learn at the beginning of his rookie year.
Unfortunately the Titans probably aren't going to have the luxury of letting first round draft pick Jake Locker sit on the bench. The Titans will bring in a veteran quarterback to compete with Locker, but we have to assume at this point it will via free agency not via trade, and the list of guys that will be available as free agents is pretty terrible.
That means that this team is probably going to be pretty bad early, and here will be a lot of pressure on Mike Munchak and company to get Locker in the game if the team isn't winning. Munch might be able to withstand that for a few weeks, but he will have to give in sooner than later.
The key for Locker will be putting the work in between now and then to know the offense inside and out. He seems like a guy that is going to be willing to put the work in, both in the field and in the film room, and we all know that is the key to being a successful NFL quarterback.