Better to upgrade and be able to use Openindiana on ZFS then to install..
Solaris11 is closed source and locks you in , folks. Do no install it on bare metal directly. For kernel and base system, that is Proprietary OS for OS/Net components (core system). Rest of software consolidations remain open due to GPL and other open licenses and are used in OpenIndiana distribution , that have no restrictions to use (Solaris11 licence cost 1000USD/Year/2socket)
OpenSolaris continuation is called: OPENINDIANA, (www.openindiana.org) - Solaris 11 is Oracle's closed source fork.
You can use Openindiana without paying license fees to Oracle and it uses ILLUMOS core SunOS OS/Net (www.illumos.org), also used in Nexenta and Joyent, who among others contribute to open development of the system.
If you want to try out S11, be sure NOT to install on bare machine / or Virtualized server / from S11 media!
That way you well lose ability to run Open Source OS like OpenIndiana/Illumos, because Oracle made ZFS changes that actually locks you in Oracle proprietary solution (they do not release disk format changes for oracle fork of ZFS.
But if you UPGRADE from previous system, retaining ZFS version on-disk, then you can use sam disk(s) rpool in multiple Boot environments (BE's) to have mutliple OS'es that use ZFS on same partition/disk(s) at the same time.
*** HOW to install using upgrade to remain compatible for ZFS file system: ***
Best course of action is to first install from latest OpenSolaris snv_134 dev release (Get it from www.genunix.org , scroll down to "Thur Mar 11 2010" ) and after that you can both upgrade to OpenIndiana in its new Boot environment
and also you can upgrade to Solaris 11 express from snv_134 and after that - you can upgrade also from snv_134 to S11express and to S11 after that if you wish. (on same disks)
That way, ZFS will remain in version that is usable to all ZFS implementations - Osol, OpenIndiana/Illumos, Nexenta, Linux kernel module (ubuntu PPA for kernel ZFS available to add during install) ,Zfs-Fuse and FreeBSD
Or you can just install from OpenIndiana and have ZFS usable with all other open implementations and forget Oracle's closed source thing.
For chat, you can join #openindiana, #opensolaris and #illumos IRC channels on Freenode.net. Oh yes, and #solaris - requires freenode registered account. Also there are openindiana.org and opensolaris.org mailing lists.
Multiple OS install on ZFS through upgrade from openSolaris snv_134
It is much better to develop on open platform where you can actually contribute and make difference and chage anything you like. (like OpenIndiana/Illumos)
S11 is more like testbed for software vendors, it is not usable in production environment since updates are available only for subscribers.
You lock yourself in with S11 ZFS.
BUT if you get through upgrade from OpenSolaris, you can have both OpenIndiana and S11 on same zpool of disk(s) (And Linux and freeBSD if you want) at the SAME time, as separate datasets/Boot environments,
and THAT is where the fun is :)
Qemu, kvm, containers, and so on...
Qemu is not comparable to containers; it was originally intended to run Linux/x86 programs on other architectures, via emulation + syscall translation. Some work has been done to make it a full VM, via Xen, KVM, or kqemu (most FOSS VM solutions are based on it) but it is also used for full-on emulation, and it still runs userland code on Linux systems of different architectures (eg, ARM binaries on an x86 kernel).
It is a sort of catch-all for emulation; it addreses a different problem (it would parallel x86 containers on a sparc processor, in one mode).
Xen/Qemu (especially using paravirtualization) might be somewhat similar.
But Qemu is actually the base for VirtualBox-that should give an idea of what it does.
Virtual networking? Do you mean like TUN/TAP (since late in the 2.1.x series)? Or like virtio? or like slirp? or like something else?
We have so many different approaches it gets confusing very quick.
For containers Linux has a copy--OpenVZ. It may be somewhat heavier on disk requirements, though Oracle btrfs (or another COW type FS) might help with that :-P
This is the successor project to the "Linux vServer" referred to on the Zones & Containers page.
We don't really have a perfect match for pfexec, though sudo can be made to work somewhat close. And the dtrace 'equivalents' aren't quite a match. But saying that only Solaris has the virtualization features is not justified--Linux has quite a few of those.