Does anyone really use "save" so infrequently that they have not memorized the keyboard shortcut? There's a reason no apps on OS X have save icons...

They mentioned they dumped the clipboard buttons because nobody uses them. I would guess the need with Visual Studio isn't so much "Save" but "Save All", which also updates various project files. (I don't know the Save All shortcut off the top of my head - I almost always use the toolbar button.)

SaveAll is Ctrl-Shift-S on most programs.

How about a picture of the inside of a magnetic media hard drive, complete with platters and heads. Or maybe just an icon of a bare 3.5" drive unit.

http://www.ubuntu.com/tour/img/librewriter.jpg

Everyone should be able to relate to that, right? :-)

an appropriate metaphor that represents checking your code in to your favored version control repository.