Gluster users - Jun 2012 - Gluster in cloud environments

Hi,

My experience with Gluster has been entirely with local hardware. And the
discussion here has been entirely about such use. But I the Gluster docs
hint of Gluster use within cloud environments - or at least in Amazon's.
Note this is a different issue than using Gluster as backing storage for a
private clould. (Exciting that it might finally be good for VMs - I look
forward to testing that - but it's a different issue.)

Currently on the Gluster site there's mention of the Red Hat Cloud
Appliance for Amazon, with a link to this article:

http://www.wired.com/cloudline/2012/02/red-hat-cloud-appliance/

The article mentions the usefulness of Posix compliance. That and
replication features have obvious use. But I'm not asking about an appliance
here, nor Amazon's cloud. What I'm wondering about is uses of Gluster
based
on a generic VM (RH, CentOS, Ubuntu, Debian ... whatever), on top of brand X
clouds. In this instance one by a backwater provider that promises:

    VMware's vSphere 4 virtualization platform
    Cisco Unified Computing System (UCS)
    IBM XiV storage
    Mezeo Cloud Storage platform
    DoubleTake DR and replication software

Avoiding DoubleTake, an expensive option, could be a real advantage with
Gluster, since we'd do well to maintain fail-back capability to our current
office if the whole cloud thing blows up - where we've already got (older)
Gluster handling vital parts of our storage. But I've no clear picture of
how vSphere fits with XiV fits with Mezeo - and whether Gluster can be a
useful compliment there.

Thanks,
Whit