Are snapshots possible?

I've been creating and deploying images The Old Way, and am beginning to see the light. That said, I have a few images which are perfect as they are and would like to keep them but apply the new concepts moving forward. I tried using my existing image as a base but it continues to look for an actual OS X install disc instead. In addition to my current need, wouldn't it be beneficial to allow for snapshot images so that we don't have to continually install the same updates and patches every time we build an image?