Currently, DV does not have actual email templates, even though they call them that. What they have is saved emails. Actual templates would be extremely helpful.
An actual template does not retain any variable content. Rather, it retains only those features which you want to remain constant across different mailings, such as headers, footers, images, color schemes, fonts, signatures, and such. It would be very helpful if we could actually create real templates, separate from any particular mailing or mailings, where these constants are stored and pull them up to add content to them without making any changes to the underlying templates themselves.
As it is, we don't actually have any templates at all, just old emails. I like having the old emails saved, but they should be in a searchable archive, not used as a stand-in for actual email templates.
I would like to see this feature updated as Paul has outlined.