[ostree] docs/introduction: Note VMs vs baremetal

[Colin Walters <walters src gnome org>]

commit 7ace5d35bd8b9d4d407b725518497df425376573
Author: Colin Walters <walters verbum org>
Date:   Thu Mar 3 14:20:44 2016 -0500

    docs/introduction: Note VMs vs baremetal

 docs/manual/introduction.md |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/docs/manual/introduction.md b/docs/manual/introduction.md
index b0d4739..b9c69c2 100644
--- a/docs/manual/introduction.md
+++ b/docs/manual/introduction.md
@@ -79,6 +79,13 @@ filesystem that supports hard links.  Note: OSTree will
 transparently take advantage of some BTRFS features if deployed
 on it.
 
+OSTree is orthogonal to virtualization mechanisms like AMIs and qcow2
+images, though it's most useful though if you plan to update stateful
+VMs in-place, rather than generating new images.
+
+In practice, users of "bare metal" configurations will find the OSTree
+model most useful.
+
 ## Atomic transitions between parallel-installable read-only filesystem trees
 
 Another deeply fundamental difference between both package