"Yost points to upgrades in the rotation (acquiring Jonathan Sanchez in a trade with San Francisco and retaining Bruce Chen) and the bullpen (signing two-time All-Star Jonathan Broxton) as further reasons to expect major on-field improvement." -Bob Dutton of the Kansas City Star
Just as some food for thought here's a few table displaying some various WARs values of last year's players and this years. I chose to use Wood in the first set, because if Crow were to stay in the rotation, I believe Wood would be the most likely to lose his roster spot.
For the weighted averages, I applied a 50% weight to last season, 30% to 2010, and 20% for 2009. Obviously some players didn't play in each of these season so they were assigned a value of 0.
For this set I used Aaron Crow. I believe that if the Royals do transition him to the rotation, it will likely result in a step back, meaning he would spend time in Omaha developing as a starter. This would mean Broxton would take Crow's spot on the big league team for the time being.
I think the Royals are definitely buying potential here. The potential in future success for the players on the right are likely higher than the players on the left. However, as you can see these moves definitely don't make the Royals obviously better for 2012 and there is the possibility that by investing into potential the Royals could actually take a step back this upcoming season.