The new F-Series is already on sale and shipping in Europe, but this doesn't seem to be the case in the rest of the world. It seems that the Asia Pacific region will have the new Walkman starting this December as stated in this pdf. Unlike in Europe though, the Asia Pacific region will have a 32GB and a 64GB version.
I'm still undecided whether I will be purchasing the new F-Series or opting for a noise cancellation headset to pair with my Z1.
Thanks to sealplayerz for the information.