If the leak is accurate it compares the Zen, on the right, with AMD's upcoming and last Clustered Multithreading / CMT CPU core code named Excavator.Excavator is the last of AMD's Bulldozer family of cores and it will appear with AMD's Carrizo APU, which AMD claims will be the most power efficient mainstream APU.
Zen takes a more traditional AMD CPU layout similar to Phenom. There appears to be one integer cluster in a Zen core while there are two as in the Excavator. Bulldozer had a high integer throughput at the expense of floating point performance.