Q:

Difference between virtualbox + vagrant and VMWare fusion

I've been running VMWare fusion for awhile now and use it to create new instances of my ubuntu rails dev environment and web server.
I'm trying to transition over to using virtualbox and vagrant.
From what I understand, virtualbox runs the VM and vagrant manages the instances. In VMWare Fusion it does both the VM and instance management. Does that mean using virtualbox with vagrant is pretty much the same as just using VMWare Fusion? 

A:

Yes your bolded last question is correct.  Vagrant is a fantastic tool in which to wrap up and define a VM as a config file.  VirtualBox does the heavy lifting as well as the deployers (puppet, chef).  As the author says, he stands on the shoulders of giants.  I'd want to move off fusion if your are sick of wiping your env clean or if you want a really pristine staging env.  Use fusion for a permanent box or to run an X11 GUI.  Vagrant can also repackage your vm after you have built it.  So you can use someone's base image and repack it. VMware can do this too but not easily from a config file afaik.
Vagrant seems to stop short of capify but it's not tied to rails/ruby.  I mean, I would just use it for staging and dev solo or dev teams.  Maybe not prod provisioning.
VirtualBox compares directly with VMWare.  Once vagrant hits 1.0 it is planned that it will support vmware fusion and then you'll have a choice of vm platform.
Also take a look at librarian-chef as related to vagrant.  Pretty cool set of premade cookbooks for chef.

