When you export as bitmap a document from a design program, you often want to export it several times. I'd love Inkscape to have a checkbox in the export-as-bitmap dialog that says "and export every time I save". Another file-menu-command such as "export-again" would also help.
Such automation is not well-suited for the GUI. Doing something that I did not explicitly ask it to do, perhaps long after I set "export with save" for some objects and have forgotten about that, might be a nasty surpise. Instead automating export is a good task for the command line interface, and in CVS we have a lot of improvements on that. Most importantly, you can now specify the id of the object on the command line and that object will get exported with the same filename and dpi as you used for it last time in the GUI. So you can easily do a shell script or batch file to export e.g. all buttons from a web page mockup with one command. More details here:
http://inkscape.org/cgi-bin/wiki.pl?ReleaseNotes
And maybe "settings-set-for-export" may make sense (at least in some future).
What is this? Filename and dpi are remembered for each exported object, if that is what you mean.