Just read a piece by Marco Ament about doing away with save as a concept in OSX applications:
I'd argue — and I think, with iOS and Lion, Apple has shown that they agree — that rather than rethinking the icon, we should abandon the concept of explicitly saving files. Modern computers have more than enough disk space and RAM to implement per-file versioning and aggressive autosaving for almost all common document types. (And it looks like Lion implements that.)
Normally I find myself nodding in agreement when reading Marco's opinions but for once I am not. I'm all in favour of autosave to ensure that work isn't lost but, at the same time, I find the idea of not having an explicit save option is a step too far.
In the first place work-in-progress may not be valid/coherent. Do I want it saved? If there is no explicit save then there is no difference work-in-progress that I want and work-in-progress that I don't want.
Further, without save, how do I mark a "finished" item? It seems like any alternative metaphor I can think of is just save by another name.
I'm not convinced saves day is done.