- Xen is currently not supported by the kernel Debian Installer uses (though
work is being done to change that.
- KVM AFAIK requires hardware support that I don't have.
- QEMU is completely useless because of its slow speed without the (also out
of tree) kqemu module, which does not work when the host system is x86_64
[1]. Also, I very much prefer the VirtualBox user interface over what qemu
has to offer.
- I've actually used VMWare for a long time (licenced), but stopped after
the 5 series stopped working with current kernels and around that time
VirtualBox became available as an alternative.
Hope that explains.
Cheers,
FJP
[1] http://bugs.debian.org/444160
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