The committee picks not only the 4 playoff teams, but also the 8 teams in the other 4 major bowl games.
So this year, the playoffs would have likely been 1. FSU v. 4. MSU and 2. Auburn v. 3. Alabama. If the 4 traditional BCS bowls were still the same the match-ups would have looked something like this: Ohio State and Stanford would have been matched in the Rose Bowl to keep the tie ins. Clemson would have been in the Orange. Baylor would have been in the Fiesta. Missouri would have been in the Sugar. Those are tie in type games. The committee then would have placed Central Florida (AQ this year or highest ranked non-AQ champion next year), and likely Oklahoma and South Carolina in the three games. I would imagine that South Carolina would have been matched against Baylor (to avoid rematches in the other two) and given locations of the other two teams and bowl games, Oklahoma would have faced Missouri and Central Florida would have faced Clemson. Now it won't always work out that way with the other locations being included.