The relevant snippet from my conversation with DH:
> It is easy/painless to migrate from Shared to PS, and no or little
> intervention is needed from the Dreamhost side (i.e. I can do it myself
> using the provided control panel tools)
DH: Correct!
> However to switch from PS to
> Shared is a manual process, needs to be conducted by DH staff, and
> depending on the particular applications running on a site may not even
> be possible without trimming and/or dropping some features.
DH: This is also true. We just have to make sure that you're ready to play
nice with the other users on the machine, that's all!
> Has anyone tried Plone on one of these yet?
DH: Not that I have heard of, but it is known to be just a bit CPU intensive.
You're going to want to start this application on a DreamHost PS, as I
don't see it playing too well with the other users on a shared system.
Please let me know if you need anything else!
--matt