spice is a next-generation remote desktop protocol, aimed at virtual
machines.
focus is not just on display/input devices, but clipboard, audio,
video, opengl, smartcards, usb devices as well, no matter if the
virtual machine runs locally or on a remote host.
not everything is implemented yet, and I didn't enable all available
features yet.
Currently, spice is able to make qemu-kvm virtual machines very usable
for workstation guests, with good 2d video support, clipboard sharing,
full resolutions, auto-mouse-grab/ungrab, xinerama / multiple guest
monitors. Good drivers for windows 7 guests are available, as well as
linux Xorg drivers / agents.
Basically, kvm was already the best-performing VM solution (using
virtio drivers), but virtualbox, while slower, had better
desktop-integration support (still wins if you want opengl). Spice
fixes this, making the choice very easy.
