With Fedora 19 the updated desktop options are GNOME 3.8, KDE Plasma 4.10, and MATE 1.6 along with existing options like Xfce 4.10 and LXDE. Some new features to Fedora 19 Alpha include syslinux boot tool integration support as an option instead of GRUB, systemd resource control, checkpoint and restore support, improvements to virtual storage migration, OpenShift Origin support, support for the Scratch programming environment, and many other features. Fedora 19 also brings a lot of other new features.
The lengthy Fedora 19 Alpha release announcement can be found on this mailing list.
The final release of Fedora 19 is expected in early July while the Fedora 19 Beta is tentatively anticipated for late May.